From c4fdfabcc8ea3f6186d1560f7756211fce125be3 Mon Sep 17 00:00:00 2001
From: naruse <naruse@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Wed, 16 Dec 2015 05:31:54 +0000
Subject: handle ext/ as r53141

g -L frozen_string_literal ext/**/*.rb|xargs ruby -Ka -e'ARGV.each{|fn|puts
fn;open(fn,"r+"){|f|s=f.read.sub(/\A(#!.*\n)?(#.*coding.*\n)?/,"\\&#
frozen_string_literal: false\n");f.rewind;f.write s}}'

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53143 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ext/tk/lib/multi-tk.rb                                 | 1 +
 ext/tk/lib/remote-tk.rb                                | 1 +
 ext/tk/lib/tcltk.rb                                    | 1 +
 ext/tk/lib/tk.rb                                       | 1 +
 ext/tk/lib/tk/after.rb                                 | 1 +
 ext/tk/lib/tk/autoload.rb                              | 1 +
 ext/tk/lib/tk/bgerror.rb                               | 1 +
 ext/tk/lib/tk/bindtag.rb                               | 1 +
 ext/tk/lib/tk/busy.rb                                  | 1 +
 ext/tk/lib/tk/button.rb                                | 1 +
 ext/tk/lib/tk/canvas.rb                                | 1 +
 ext/tk/lib/tk/canvastag.rb                             | 1 +
 ext/tk/lib/tk/checkbutton.rb                           | 1 +
 ext/tk/lib/tk/clipboard.rb                             | 1 +
 ext/tk/lib/tk/clock.rb                                 | 1 +
 ext/tk/lib/tk/composite.rb                             | 1 +
 ext/tk/lib/tk/console.rb                               | 1 +
 ext/tk/lib/tk/dialog.rb                                | 1 +
 ext/tk/lib/tk/encodedstr.rb                            | 1 +
 ext/tk/lib/tk/entry.rb                                 | 1 +
 ext/tk/lib/tk/event.rb                                 | 1 +
 ext/tk/lib/tk/font.rb                                  | 1 +
 ext/tk/lib/tk/fontchooser.rb                           | 1 +
 ext/tk/lib/tk/frame.rb                                 | 1 +
 ext/tk/lib/tk/grid.rb                                  | 1 +
 ext/tk/lib/tk/image.rb                                 | 1 +
 ext/tk/lib/tk/itemconfig.rb                            | 1 +
 ext/tk/lib/tk/itemfont.rb                              | 1 +
 ext/tk/lib/tk/kinput.rb                                | 1 +
 ext/tk/lib/tk/label.rb                                 | 1 +
 ext/tk/lib/tk/labelframe.rb                            | 1 +
 ext/tk/lib/tk/listbox.rb                               | 1 +
 ext/tk/lib/tk/macpkg.rb                                | 1 +
 ext/tk/lib/tk/menu.rb                                  | 1 +
 ext/tk/lib/tk/menubar.rb                               | 1 +
 ext/tk/lib/tk/menuspec.rb                              | 1 +
 ext/tk/lib/tk/message.rb                               | 1 +
 ext/tk/lib/tk/mngfocus.rb                              | 1 +
 ext/tk/lib/tk/msgcat.rb                                | 1 +
 ext/tk/lib/tk/namespace.rb                             | 1 +
 ext/tk/lib/tk/optiondb.rb                              | 1 +
 ext/tk/lib/tk/optionobj.rb                             | 1 +
 ext/tk/lib/tk/pack.rb                                  | 1 +
 ext/tk/lib/tk/package.rb                               | 1 +
 ext/tk/lib/tk/palette.rb                               | 1 +
 ext/tk/lib/tk/panedwindow.rb                           | 1 +
 ext/tk/lib/tk/place.rb                                 | 1 +
 ext/tk/lib/tk/radiobutton.rb                           | 1 +
 ext/tk/lib/tk/root.rb                                  | 1 +
 ext/tk/lib/tk/scale.rb                                 | 1 +
 ext/tk/lib/tk/scrollable.rb                            | 1 +
 ext/tk/lib/tk/scrollbar.rb                             | 1 +
 ext/tk/lib/tk/scrollbox.rb                             | 1 +
 ext/tk/lib/tk/selection.rb                             | 1 +
 ext/tk/lib/tk/spinbox.rb                               | 1 +
 ext/tk/lib/tk/tagfont.rb                               | 1 +
 ext/tk/lib/tk/text.rb                                  | 1 +
 ext/tk/lib/tk/textimage.rb                             | 1 +
 ext/tk/lib/tk/textmark.rb                              | 1 +
 ext/tk/lib/tk/texttag.rb                               | 1 +
 ext/tk/lib/tk/textwindow.rb                            | 1 +
 ext/tk/lib/tk/timer.rb                                 | 1 +
 ext/tk/lib/tk/tk_mac.rb                                | 1 +
 ext/tk/lib/tk/toplevel.rb                              | 1 +
 ext/tk/lib/tk/ttk_selector.rb                          | 1 +
 ext/tk/lib/tk/txtwin_abst.rb                           | 1 +
 ext/tk/lib/tk/validation.rb                            | 1 +
 ext/tk/lib/tk/variable.rb                              | 1 +
 ext/tk/lib/tk/virtevent.rb                             | 1 +
 ext/tk/lib/tk/winfo.rb                                 | 1 +
 ext/tk/lib/tk/winpkg.rb                                | 1 +
 ext/tk/lib/tk/wm.rb                                    | 1 +
 ext/tk/lib/tk/xim.rb                                   | 1 +
 ext/tk/lib/tkafter.rb                                  | 1 +
 ext/tk/lib/tkbgerror.rb                                | 1 +
 ext/tk/lib/tkcanvas.rb                                 | 1 +
 ext/tk/lib/tkclass.rb                                  | 1 +
 ext/tk/lib/tkconsole.rb                                | 1 +
 ext/tk/lib/tkdialog.rb                                 | 1 +
 ext/tk/lib/tkentry.rb                                  | 1 +
 ext/tk/lib/tkextlib/ICONS.rb                           | 1 +
 ext/tk/lib/tkextlib/ICONS/icons.rb                     | 1 +
 ext/tk/lib/tkextlib/ICONS/setup.rb                     | 1 +
 ext/tk/lib/tkextlib/blt.rb                             | 1 +
 ext/tk/lib/tkextlib/blt/barchart.rb                    | 1 +
 ext/tk/lib/tkextlib/blt/bitmap.rb                      | 1 +
 ext/tk/lib/tkextlib/blt/busy.rb                        | 1 +
 ext/tk/lib/tkextlib/blt/component.rb                   | 1 +
 ext/tk/lib/tkextlib/blt/container.rb                   | 1 +
 ext/tk/lib/tkextlib/blt/cutbuffer.rb                   | 1 +
 ext/tk/lib/tkextlib/blt/dragdrop.rb                    | 1 +
 ext/tk/lib/tkextlib/blt/eps.rb                         | 1 +
 ext/tk/lib/tkextlib/blt/graph.rb                       | 1 +
 ext/tk/lib/tkextlib/blt/htext.rb                       | 1 +
 ext/tk/lib/tkextlib/blt/setup.rb                       | 1 +
 ext/tk/lib/tkextlib/blt/spline.rb                      | 1 +
 ext/tk/lib/tkextlib/blt/stripchart.rb                  | 1 +
 ext/tk/lib/tkextlib/blt/table.rb                       | 1 +
 ext/tk/lib/tkextlib/blt/tabnotebook.rb                 | 1 +
 ext/tk/lib/tkextlib/blt/tabset.rb                      | 1 +
 ext/tk/lib/tkextlib/blt/ted.rb                         | 1 +
 ext/tk/lib/tkextlib/blt/tile.rb                        | 1 +
 ext/tk/lib/tkextlib/blt/tile/button.rb                 | 1 +
 ext/tk/lib/tkextlib/blt/tile/checkbutton.rb            | 1 +
 ext/tk/lib/tkextlib/blt/tile/frame.rb                  | 1 +
 ext/tk/lib/tkextlib/blt/tile/label.rb                  | 1 +
 ext/tk/lib/tkextlib/blt/tile/radiobutton.rb            | 1 +
 ext/tk/lib/tkextlib/blt/tile/scrollbar.rb              | 1 +
 ext/tk/lib/tkextlib/blt/tile/toplevel.rb               | 1 +
 ext/tk/lib/tkextlib/blt/tree.rb                        | 1 +
 ext/tk/lib/tkextlib/blt/treeview.rb                    | 1 +
 ext/tk/lib/tkextlib/blt/unix_dnd.rb                    | 1 +
 ext/tk/lib/tkextlib/blt/vector.rb                      | 1 +
 ext/tk/lib/tkextlib/blt/watch.rb                       | 1 +
 ext/tk/lib/tkextlib/blt/win_printer.rb                 | 1 +
 ext/tk/lib/tkextlib/blt/winop.rb                       | 1 +
 ext/tk/lib/tkextlib/bwidget.rb                         | 1 +
 ext/tk/lib/tkextlib/bwidget/arrowbutton.rb             | 1 +
 ext/tk/lib/tkextlib/bwidget/bitmap.rb                  | 1 +
 ext/tk/lib/tkextlib/bwidget/button.rb                  | 1 +
 ext/tk/lib/tkextlib/bwidget/buttonbox.rb               | 1 +
 ext/tk/lib/tkextlib/bwidget/combobox.rb                | 1 +
 ext/tk/lib/tkextlib/bwidget/dialog.rb                  | 1 +
 ext/tk/lib/tkextlib/bwidget/dragsite.rb                | 1 +
 ext/tk/lib/tkextlib/bwidget/dropsite.rb                | 1 +
 ext/tk/lib/tkextlib/bwidget/dynamichelp.rb             | 1 +
 ext/tk/lib/tkextlib/bwidget/entry.rb                   | 1 +
 ext/tk/lib/tkextlib/bwidget/label.rb                   | 1 +
 ext/tk/lib/tkextlib/bwidget/labelentry.rb              | 1 +
 ext/tk/lib/tkextlib/bwidget/labelframe.rb              | 1 +
 ext/tk/lib/tkextlib/bwidget/listbox.rb                 | 1 +
 ext/tk/lib/tkextlib/bwidget/mainframe.rb               | 1 +
 ext/tk/lib/tkextlib/bwidget/messagedlg.rb              | 1 +
 ext/tk/lib/tkextlib/bwidget/notebook.rb                | 1 +
 ext/tk/lib/tkextlib/bwidget/pagesmanager.rb            | 1 +
 ext/tk/lib/tkextlib/bwidget/panedwindow.rb             | 1 +
 ext/tk/lib/tkextlib/bwidget/panelframe.rb              | 1 +
 ext/tk/lib/tkextlib/bwidget/passwddlg.rb               | 1 +
 ext/tk/lib/tkextlib/bwidget/progressbar.rb             | 1 +
 ext/tk/lib/tkextlib/bwidget/progressdlg.rb             | 1 +
 ext/tk/lib/tkextlib/bwidget/scrollableframe.rb         | 1 +
 ext/tk/lib/tkextlib/bwidget/scrolledwindow.rb          | 1 +
 ext/tk/lib/tkextlib/bwidget/scrollview.rb              | 1 +
 ext/tk/lib/tkextlib/bwidget/selectcolor.rb             | 1 +
 ext/tk/lib/tkextlib/bwidget/selectfont.rb              | 1 +
 ext/tk/lib/tkextlib/bwidget/separator.rb               | 1 +
 ext/tk/lib/tkextlib/bwidget/setup.rb                   | 1 +
 ext/tk/lib/tkextlib/bwidget/spinbox.rb                 | 1 +
 ext/tk/lib/tkextlib/bwidget/statusbar.rb               | 1 +
 ext/tk/lib/tkextlib/bwidget/titleframe.rb              | 1 +
 ext/tk/lib/tkextlib/bwidget/tree.rb                    | 1 +
 ext/tk/lib/tkextlib/bwidget/widget.rb                  | 1 +
 ext/tk/lib/tkextlib/itcl.rb                            | 1 +
 ext/tk/lib/tkextlib/itcl/incr_tcl.rb                   | 1 +
 ext/tk/lib/tkextlib/itcl/setup.rb                      | 1 +
 ext/tk/lib/tkextlib/itk.rb                             | 1 +
 ext/tk/lib/tkextlib/itk/incr_tk.rb                     | 1 +
 ext/tk/lib/tkextlib/itk/setup.rb                       | 1 +
 ext/tk/lib/tkextlib/iwidgets.rb                        | 1 +
 ext/tk/lib/tkextlib/iwidgets/buttonbox.rb              | 1 +
 ext/tk/lib/tkextlib/iwidgets/calendar.rb               | 1 +
 ext/tk/lib/tkextlib/iwidgets/canvasprintbox.rb         | 1 +
 ext/tk/lib/tkextlib/iwidgets/canvasprintdialog.rb      | 1 +
 ext/tk/lib/tkextlib/iwidgets/checkbox.rb               | 1 +
 ext/tk/lib/tkextlib/iwidgets/combobox.rb               | 1 +
 ext/tk/lib/tkextlib/iwidgets/dateentry.rb              | 1 +
 ext/tk/lib/tkextlib/iwidgets/datefield.rb              | 1 +
 ext/tk/lib/tkextlib/iwidgets/dialog.rb                 | 1 +
 ext/tk/lib/tkextlib/iwidgets/dialogshell.rb            | 1 +
 ext/tk/lib/tkextlib/iwidgets/disjointlistbox.rb        | 1 +
 ext/tk/lib/tkextlib/iwidgets/entryfield.rb             | 1 +
 ext/tk/lib/tkextlib/iwidgets/extbutton.rb              | 1 +
 ext/tk/lib/tkextlib/iwidgets/extfileselectionbox.rb    | 1 +
 ext/tk/lib/tkextlib/iwidgets/extfileselectiondialog.rb | 1 +
 ext/tk/lib/tkextlib/iwidgets/feedback.rb               | 1 +
 ext/tk/lib/tkextlib/iwidgets/fileselectionbox.rb       | 1 +
 ext/tk/lib/tkextlib/iwidgets/fileselectiondialog.rb    | 1 +
 ext/tk/lib/tkextlib/iwidgets/finddialog.rb             | 1 +
 ext/tk/lib/tkextlib/iwidgets/hierarchy.rb              | 1 +
 ext/tk/lib/tkextlib/iwidgets/hyperhelp.rb              | 1 +
 ext/tk/lib/tkextlib/iwidgets/labeledframe.rb           | 1 +
 ext/tk/lib/tkextlib/iwidgets/labeledwidget.rb          | 1 +
 ext/tk/lib/tkextlib/iwidgets/mainwindow.rb             | 1 +
 ext/tk/lib/tkextlib/iwidgets/menubar.rb                | 1 +
 ext/tk/lib/tkextlib/iwidgets/messagebox.rb             | 1 +
 ext/tk/lib/tkextlib/iwidgets/messagedialog.rb          | 1 +
 ext/tk/lib/tkextlib/iwidgets/notebook.rb               | 1 +
 ext/tk/lib/tkextlib/iwidgets/optionmenu.rb             | 1 +
 ext/tk/lib/tkextlib/iwidgets/panedwindow.rb            | 1 +
 ext/tk/lib/tkextlib/iwidgets/promptdialog.rb           | 1 +
 ext/tk/lib/tkextlib/iwidgets/pushbutton.rb             | 1 +
 ext/tk/lib/tkextlib/iwidgets/radiobox.rb               | 1 +
 ext/tk/lib/tkextlib/iwidgets/scopedobject.rb           | 1 +
 ext/tk/lib/tkextlib/iwidgets/scrolledcanvas.rb         | 1 +
 ext/tk/lib/tkextlib/iwidgets/scrolledframe.rb          | 1 +
 ext/tk/lib/tkextlib/iwidgets/scrolledhtml.rb           | 1 +
 ext/tk/lib/tkextlib/iwidgets/scrolledlistbox.rb        | 1 +
 ext/tk/lib/tkextlib/iwidgets/scrolledtext.rb           | 1 +
 ext/tk/lib/tkextlib/iwidgets/scrolledwidget.rb         | 1 +
 ext/tk/lib/tkextlib/iwidgets/selectionbox.rb           | 1 +
 ext/tk/lib/tkextlib/iwidgets/selectiondialog.rb        | 1 +
 ext/tk/lib/tkextlib/iwidgets/setup.rb                  | 1 +
 ext/tk/lib/tkextlib/iwidgets/shell.rb                  | 1 +
 ext/tk/lib/tkextlib/iwidgets/spindate.rb               | 1 +
 ext/tk/lib/tkextlib/iwidgets/spinint.rb                | 1 +
 ext/tk/lib/tkextlib/iwidgets/spinner.rb                | 1 +
 ext/tk/lib/tkextlib/iwidgets/spintime.rb               | 1 +
 ext/tk/lib/tkextlib/iwidgets/tabnotebook.rb            | 1 +
 ext/tk/lib/tkextlib/iwidgets/tabset.rb                 | 1 +
 ext/tk/lib/tkextlib/iwidgets/timeentry.rb              | 1 +
 ext/tk/lib/tkextlib/iwidgets/timefield.rb              | 1 +
 ext/tk/lib/tkextlib/iwidgets/toolbar.rb                | 1 +
 ext/tk/lib/tkextlib/iwidgets/watch.rb                  | 1 +
 ext/tk/lib/tkextlib/pkg_checker.rb                     | 1 +
 ext/tk/lib/tkextlib/setup.rb                           | 1 +
 ext/tk/lib/tkextlib/tcllib.rb                          | 1 +
 ext/tk/lib/tkextlib/tcllib/autoscroll.rb               | 1 +
 ext/tk/lib/tkextlib/tcllib/calendar.rb                 | 1 +
 ext/tk/lib/tkextlib/tcllib/canvas_sqmap.rb             | 1 +
 ext/tk/lib/tkextlib/tcllib/canvas_zoom.rb              | 1 +
 ext/tk/lib/tkextlib/tcllib/chatwidget.rb               | 1 +
 ext/tk/lib/tkextlib/tcllib/crosshair.rb                | 1 +
 ext/tk/lib/tkextlib/tcllib/ctext.rb                    | 1 +
 ext/tk/lib/tkextlib/tcllib/cursor.rb                   | 1 +
 ext/tk/lib/tkextlib/tcllib/dateentry.rb                | 1 +
 ext/tk/lib/tkextlib/tcllib/datefield.rb                | 1 +
 ext/tk/lib/tkextlib/tcllib/diagrams.rb                 | 1 +
 ext/tk/lib/tkextlib/tcllib/dialog.rb                   | 1 +
 ext/tk/lib/tkextlib/tcllib/getstring.rb                | 1 +
 ext/tk/lib/tkextlib/tcllib/history.rb                  | 1 +
 ext/tk/lib/tkextlib/tcllib/ico.rb                      | 1 +
 ext/tk/lib/tkextlib/tcllib/ip_entry.rb                 | 1 +
 ext/tk/lib/tkextlib/tcllib/khim.rb                     | 1 +
 ext/tk/lib/tkextlib/tcllib/menuentry.rb                | 1 +
 ext/tk/lib/tkextlib/tcllib/ntext.rb                    | 1 +
 ext/tk/lib/tkextlib/tcllib/panelframe.rb               | 1 +
 ext/tk/lib/tkextlib/tcllib/plotchart.rb                | 1 +
 ext/tk/lib/tkextlib/tcllib/ruler.rb                    | 1 +
 ext/tk/lib/tkextlib/tcllib/screenruler.rb              | 1 +
 ext/tk/lib/tkextlib/tcllib/scrolledwindow.rb           | 1 +
 ext/tk/lib/tkextlib/tcllib/scrollwin.rb                | 1 +
 ext/tk/lib/tkextlib/tcllib/setup.rb                    | 1 +
 ext/tk/lib/tkextlib/tcllib/statusbar.rb                | 1 +
 ext/tk/lib/tkextlib/tcllib/style.rb                    | 1 +
 ext/tk/lib/tkextlib/tcllib/superframe.rb               | 1 +
 ext/tk/lib/tkextlib/tcllib/swaplist.rb                 | 1 +
 ext/tk/lib/tkextlib/tcllib/tablelist.rb                | 1 +
 ext/tk/lib/tkextlib/tcllib/tablelist_core.rb           | 1 +
 ext/tk/lib/tkextlib/tcllib/tablelist_tile.rb           | 1 +
 ext/tk/lib/tkextlib/tcllib/tkpiechart.rb               | 1 +
 ext/tk/lib/tkextlib/tcllib/toolbar.rb                  | 1 +
 ext/tk/lib/tkextlib/tcllib/tooltip.rb                  | 1 +
 ext/tk/lib/tkextlib/tcllib/validator.rb                | 1 +
 ext/tk/lib/tkextlib/tcllib/widget.rb                   | 1 +
 ext/tk/lib/tkextlib/tclx.rb                            | 1 +
 ext/tk/lib/tkextlib/tclx/setup.rb                      | 1 +
 ext/tk/lib/tkextlib/tclx/tclx.rb                       | 1 +
 ext/tk/lib/tkextlib/tile.rb                            | 1 +
 ext/tk/lib/tkextlib/tile/dialog.rb                     | 1 +
 ext/tk/lib/tkextlib/tile/setup.rb                      | 1 +
 ext/tk/lib/tkextlib/tile/sizegrip.rb                   | 1 +
 ext/tk/lib/tkextlib/tile/style.rb                      | 1 +
 ext/tk/lib/tkextlib/tile/tbutton.rb                    | 1 +
 ext/tk/lib/tkextlib/tile/tcheckbutton.rb               | 1 +
 ext/tk/lib/tkextlib/tile/tcombobox.rb                  | 1 +
 ext/tk/lib/tkextlib/tile/tentry.rb                     | 1 +
 ext/tk/lib/tkextlib/tile/tframe.rb                     | 1 +
 ext/tk/lib/tkextlib/tile/tlabel.rb                     | 1 +
 ext/tk/lib/tkextlib/tile/tlabelframe.rb                | 1 +
 ext/tk/lib/tkextlib/tile/tmenubutton.rb                | 1 +
 ext/tk/lib/tkextlib/tile/tnotebook.rb                  | 1 +
 ext/tk/lib/tkextlib/tile/tpaned.rb                     | 1 +
 ext/tk/lib/tkextlib/tile/tprogressbar.rb               | 1 +
 ext/tk/lib/tkextlib/tile/tradiobutton.rb               | 1 +
 ext/tk/lib/tkextlib/tile/treeview.rb                   | 1 +
 ext/tk/lib/tkextlib/tile/tscale.rb                     | 1 +
 ext/tk/lib/tkextlib/tile/tscrollbar.rb                 | 1 +
 ext/tk/lib/tkextlib/tile/tseparator.rb                 | 1 +
 ext/tk/lib/tkextlib/tile/tspinbox.rb                   | 1 +
 ext/tk/lib/tkextlib/tile/tsquare.rb                    | 1 +
 ext/tk/lib/tkextlib/tkDND.rb                           | 1 +
 ext/tk/lib/tkextlib/tkDND/setup.rb                     | 1 +
 ext/tk/lib/tkextlib/tkDND/shape.rb                     | 1 +
 ext/tk/lib/tkextlib/tkDND/tkdnd.rb                     | 1 +
 ext/tk/lib/tkextlib/tkHTML.rb                          | 1 +
 ext/tk/lib/tkextlib/tkHTML/htmlwidget.rb               | 1 +
 ext/tk/lib/tkextlib/tkHTML/setup.rb                    | 1 +
 ext/tk/lib/tkextlib/tkimg.rb                           | 1 +
 ext/tk/lib/tkextlib/tkimg/bmp.rb                       | 1 +
 ext/tk/lib/tkextlib/tkimg/dted.rb                      | 1 +
 ext/tk/lib/tkextlib/tkimg/gif.rb                       | 1 +
 ext/tk/lib/tkextlib/tkimg/ico.rb                       | 1 +
 ext/tk/lib/tkextlib/tkimg/jpeg.rb                      | 1 +
 ext/tk/lib/tkextlib/tkimg/pcx.rb                       | 1 +
 ext/tk/lib/tkextlib/tkimg/pixmap.rb                    | 1 +
 ext/tk/lib/tkextlib/tkimg/png.rb                       | 1 +
 ext/tk/lib/tkextlib/tkimg/ppm.rb                       | 1 +
 ext/tk/lib/tkextlib/tkimg/ps.rb                        | 1 +
 ext/tk/lib/tkextlib/tkimg/raw.rb                       | 1 +
 ext/tk/lib/tkextlib/tkimg/setup.rb                     | 1 +
 ext/tk/lib/tkextlib/tkimg/sgi.rb                       | 1 +
 ext/tk/lib/tkextlib/tkimg/sun.rb                       | 1 +
 ext/tk/lib/tkextlib/tkimg/tga.rb                       | 1 +
 ext/tk/lib/tkextlib/tkimg/tiff.rb                      | 1 +
 ext/tk/lib/tkextlib/tkimg/window.rb                    | 1 +
 ext/tk/lib/tkextlib/tkimg/xbm.rb                       | 1 +
 ext/tk/lib/tkextlib/tkimg/xpm.rb                       | 1 +
 ext/tk/lib/tkextlib/tktable.rb                         | 1 +
 ext/tk/lib/tkextlib/tktable/setup.rb                   | 1 +
 ext/tk/lib/tkextlib/tktable/tktable.rb                 | 1 +
 ext/tk/lib/tkextlib/tktrans.rb                         | 1 +
 ext/tk/lib/tkextlib/tktrans/setup.rb                   | 1 +
 ext/tk/lib/tkextlib/tktrans/tktrans.rb                 | 1 +
 ext/tk/lib/tkextlib/treectrl.rb                        | 1 +
 ext/tk/lib/tkextlib/treectrl/setup.rb                  | 1 +
 ext/tk/lib/tkextlib/treectrl/tktreectrl.rb             | 1 +
 ext/tk/lib/tkextlib/trofs.rb                           | 1 +
 ext/tk/lib/tkextlib/trofs/setup.rb                     | 1 +
 ext/tk/lib/tkextlib/trofs/trofs.rb                     | 1 +
 ext/tk/lib/tkextlib/version.rb                         | 1 +
 ext/tk/lib/tkextlib/vu.rb                              | 1 +
 ext/tk/lib/tkextlib/vu/bargraph.rb                     | 1 +
 ext/tk/lib/tkextlib/vu/charts.rb                       | 1 +
 ext/tk/lib/tkextlib/vu/dial.rb                         | 1 +
 ext/tk/lib/tkextlib/vu/pie.rb                          | 1 +
 ext/tk/lib/tkextlib/vu/setup.rb                        | 1 +
 ext/tk/lib/tkextlib/vu/spinbox.rb                      | 1 +
 ext/tk/lib/tkextlib/winico.rb                          | 1 +
 ext/tk/lib/tkextlib/winico/setup.rb                    | 1 +
 ext/tk/lib/tkextlib/winico/winico.rb                   | 1 +
 ext/tk/lib/tkfont.rb                                   | 1 +
 ext/tk/lib/tkmacpkg.rb                                 | 1 +
 ext/tk/lib/tkmenubar.rb                                | 1 +
 ext/tk/lib/tkmngfocus.rb                               | 1 +
 ext/tk/lib/tkpalette.rb                                | 1 +
 ext/tk/lib/tkscrollbox.rb                              | 1 +
 ext/tk/lib/tktext.rb                                   | 1 +
 ext/tk/lib/tkvirtevent.rb                              | 1 +
 ext/tk/lib/tkwinpkg.rb                                 | 1 +
 339 files changed, 339 insertions(+)

(limited to 'ext/tk/lib')

diff --git a/ext/tk/lib/multi-tk.rb b/ext/tk/lib/multi-tk.rb
index e0f41d0f6a..a5759c70cc 100644
--- a/ext/tk/lib/multi-tk.rb
+++ b/ext/tk/lib/multi-tk.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #               multi-tk.rb - supports multi Tk interpreters
 #                       by Hidetoshi NAGAI <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/remote-tk.rb b/ext/tk/lib/remote-tk.rb
index f414489645..165e6587fd 100644
--- a/ext/tk/lib/remote-tk.rb
+++ b/ext/tk/lib/remote-tk.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #               remote-tk.rb - supports to control remote Tk interpreters
 #                       by Hidetoshi NAGAI <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tcltk.rb b/ext/tk/lib/tcltk.rb
index f8fbdfbe6d..7796bb86ef 100644
--- a/ext/tk/lib/tcltk.rb
+++ b/ext/tk/lib/tcltk.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 # tof
 
 #### tcltk library, more direct manipulation of tcl/tk
diff --git a/ext/tk/lib/tk.rb b/ext/tk/lib/tk.rb
index dd29589e86..7fe2fb0878 100644
--- a/ext/tk/lib/tk.rb
+++ b/ext/tk/lib/tk.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #               tk.rb - Tk interface module using tcltklib
 #                       by Yukihiro Matsumoto <matz@netlab.jp>
diff --git a/ext/tk/lib/tk/after.rb b/ext/tk/lib/tk/after.rb
index 8c58210331..3213a6b818 100644
--- a/ext/tk/lib/tk/after.rb
+++ b/ext/tk/lib/tk/after.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tk/after.rb : methods for Tcl/Tk after command
 #
diff --git a/ext/tk/lib/tk/autoload.rb b/ext/tk/lib/tk/autoload.rb
index 451922c7d3..3d19fb053d 100644
--- a/ext/tk/lib/tk/autoload.rb
+++ b/ext/tk/lib/tk/autoload.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  autoload
 #
diff --git a/ext/tk/lib/tk/bgerror.rb b/ext/tk/lib/tk/bgerror.rb
index c82a8e046b..9d2f59357e 100644
--- a/ext/tk/lib/tk/bgerror.rb
+++ b/ext/tk/lib/tk/bgerror.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkbgerror -- bgerror ( tkerror ) module
 #                     1998/07/16 by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/bindtag.rb b/ext/tk/lib/tk/bindtag.rb
index 23b4e0b7c3..ad3c90b505 100644
--- a/ext/tk/lib/tk/bindtag.rb
+++ b/ext/tk/lib/tk/bindtag.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/bind.rb : control event binding
 #
diff --git a/ext/tk/lib/tk/busy.rb b/ext/tk/lib/tk/busy.rb
index 7f4f89f524..18ebede9dd 100644
--- a/ext/tk/lib/tk/busy.rb
+++ b/ext/tk/lib/tk/busy.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/busy.rb: support 'tk busy' command (Tcl/Tk8.6 or later)
 #
diff --git a/ext/tk/lib/tk/button.rb b/ext/tk/lib/tk/button.rb
index 65233c91b6..dc252d8e82 100644
--- a/ext/tk/lib/tk/button.rb
+++ b/ext/tk/lib/tk/button.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/button.rb : treat button widget
 #
diff --git a/ext/tk/lib/tk/canvas.rb b/ext/tk/lib/tk/canvas.rb
index f3e9a7c229..d707733d8c 100644
--- a/ext/tk/lib/tk/canvas.rb
+++ b/ext/tk/lib/tk/canvas.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #               tk/canvas.rb - Tk canvas classes
 #                       by Yukihiro Matsumoto <matz@caelum.co.jp>
diff --git a/ext/tk/lib/tk/canvastag.rb b/ext/tk/lib/tk/canvastag.rb
index 495d92a9a8..4a14cd78a9 100644
--- a/ext/tk/lib/tk/canvastag.rb
+++ b/ext/tk/lib/tk/canvastag.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/canvastag.rb - methods for treating canvas tags
 #
diff --git a/ext/tk/lib/tk/checkbutton.rb b/ext/tk/lib/tk/checkbutton.rb
index b7449541c5..521b015b3e 100644
--- a/ext/tk/lib/tk/checkbutton.rb
+++ b/ext/tk/lib/tk/checkbutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/checkbutton.rb : treat checkbutton widget
 #
diff --git a/ext/tk/lib/tk/clipboard.rb b/ext/tk/lib/tk/clipboard.rb
index d4205a5c28..c5f481f979 100644
--- a/ext/tk/lib/tk/clipboard.rb
+++ b/ext/tk/lib/tk/clipboard.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/clipboard.rb : methods to treat clipboard
 #
diff --git a/ext/tk/lib/tk/clock.rb b/ext/tk/lib/tk/clock.rb
index 4e9438f5ab..df900d7364 100644
--- a/ext/tk/lib/tk/clock.rb
+++ b/ext/tk/lib/tk/clock.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/clock.rb : methods for clock command
 #
diff --git a/ext/tk/lib/tk/composite.rb b/ext/tk/lib/tk/composite.rb
index e267c7a22b..830d383d69 100644
--- a/ext/tk/lib/tk/composite.rb
+++ b/ext/tk/lib/tk/composite.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/composite.rb :
 #
diff --git a/ext/tk/lib/tk/console.rb b/ext/tk/lib/tk/console.rb
index 64e257594c..c560912da8 100644
--- a/ext/tk/lib/tk/console.rb
+++ b/ext/tk/lib/tk/console.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tk/console.rb : control the console on system without a real console
 #
diff --git a/ext/tk/lib/tk/dialog.rb b/ext/tk/lib/tk/dialog.rb
index 7ef7820699..0b19be7cfa 100644
--- a/ext/tk/lib/tk/dialog.rb
+++ b/ext/tk/lib/tk/dialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tk/dialog.rb : create dialog boxes
 #
diff --git a/ext/tk/lib/tk/encodedstr.rb b/ext/tk/lib/tk/encodedstr.rb
index 59fbb1911d..9ca13b3d1a 100644
--- a/ext/tk/lib/tk/encodedstr.rb
+++ b/ext/tk/lib/tk/encodedstr.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/encodedstr.rb : Tk::EncodedString class
 #
diff --git a/ext/tk/lib/tk/entry.rb b/ext/tk/lib/tk/entry.rb
index d4aa03f2b6..aa40e4755c 100644
--- a/ext/tk/lib/tk/entry.rb
+++ b/ext/tk/lib/tk/entry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #               tk/entry.rb - Tk entry classes
 #                       by Yukihiro Matsumoto <matz@caelum.co.jp>
diff --git a/ext/tk/lib/tk/event.rb b/ext/tk/lib/tk/event.rb
index bf4e122322..5658e92874 100644
--- a/ext/tk/lib/tk/event.rb
+++ b/ext/tk/lib/tk/event.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tk/event.rb - module for event
 #
diff --git a/ext/tk/lib/tk/font.rb b/ext/tk/lib/tk/font.rb
index 03db850f96..7a2a549849 100644
--- a/ext/tk/lib/tk/font.rb
+++ b/ext/tk/lib/tk/font.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tk/font.rb - the class to treat fonts on Ruby/Tk
 #
diff --git a/ext/tk/lib/tk/fontchooser.rb b/ext/tk/lib/tk/fontchooser.rb
index 6dab0c6cf9..325ca4dbd2 100644
--- a/ext/tk/lib/tk/fontchooser.rb
+++ b/ext/tk/lib/tk/fontchooser.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/fontchooser.rb -- "tk fontchooser" support (Tcl/Tk8.6 or later)
 #
diff --git a/ext/tk/lib/tk/frame.rb b/ext/tk/lib/tk/frame.rb
index 5118939732..0682faf3fe 100644
--- a/ext/tk/lib/tk/frame.rb
+++ b/ext/tk/lib/tk/frame.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/frame.rb : treat frame widget
 #
diff --git a/ext/tk/lib/tk/grid.rb b/ext/tk/lib/tk/grid.rb
index e1e07c44fa..5a4a26403a 100644
--- a/ext/tk/lib/tk/grid.rb
+++ b/ext/tk/lib/tk/grid.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/grid.rb : control grid geometry manager
 #
diff --git a/ext/tk/lib/tk/image.rb b/ext/tk/lib/tk/image.rb
index 972383982f..ec23e495d0 100644
--- a/ext/tk/lib/tk/image.rb
+++ b/ext/tk/lib/tk/image.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/image.rb : treat Tk image objects
 #
diff --git a/ext/tk/lib/tk/itemconfig.rb b/ext/tk/lib/tk/itemconfig.rb
index e8eb83d66c..e615fa0950 100644
--- a/ext/tk/lib/tk/itemconfig.rb
+++ b/ext/tk/lib/tk/itemconfig.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/itemconfig.rb : control item/tag configuration of widget
 #
diff --git a/ext/tk/lib/tk/itemfont.rb b/ext/tk/lib/tk/itemfont.rb
index b5da4fa1ef..92f75ac388 100644
--- a/ext/tk/lib/tk/itemfont.rb
+++ b/ext/tk/lib/tk/itemfont.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/itemfont.rb : control font of widget items
 #
diff --git a/ext/tk/lib/tk/kinput.rb b/ext/tk/lib/tk/kinput.rb
index b63f756def..6d2b3d7a7a 100644
--- a/ext/tk/lib/tk/kinput.rb
+++ b/ext/tk/lib/tk/kinput.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/kinput.rb : control kinput
 #
diff --git a/ext/tk/lib/tk/label.rb b/ext/tk/lib/tk/label.rb
index 05e430e49b..48f67deb31 100644
--- a/ext/tk/lib/tk/label.rb
+++ b/ext/tk/lib/tk/label.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/label.rb : treat label widget
 #
diff --git a/ext/tk/lib/tk/labelframe.rb b/ext/tk/lib/tk/labelframe.rb
index 6f679e55b5..f9497dc2f0 100644
--- a/ext/tk/lib/tk/labelframe.rb
+++ b/ext/tk/lib/tk/labelframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/labelframe.rb : treat labelframe widget
 #
diff --git a/ext/tk/lib/tk/listbox.rb b/ext/tk/lib/tk/listbox.rb
index 6742b2132c..df4d422007 100644
--- a/ext/tk/lib/tk/listbox.rb
+++ b/ext/tk/lib/tk/listbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/listbox.rb : treat listbox widget
 #
diff --git a/ext/tk/lib/tk/macpkg.rb b/ext/tk/lib/tk/macpkg.rb
index 3ca7953c13..abf9b176fb 100644
--- a/ext/tk/lib/tk/macpkg.rb
+++ b/ext/tk/lib/tk/macpkg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tk/macpkg.rb : methods for Tcl/Tk packages for Macintosh
 #                     2000/11/22 by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/menu.rb b/ext/tk/lib/tk/menu.rb
index bcd250026d..16347a98ea 100644
--- a/ext/tk/lib/tk/menu.rb
+++ b/ext/tk/lib/tk/menu.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/menu.rb : treat menu and menubutton
 #
diff --git a/ext/tk/lib/tk/menubar.rb b/ext/tk/lib/tk/menubar.rb
index 9d5571c470..17cb4477c9 100644
--- a/ext/tk/lib/tk/menubar.rb
+++ b/ext/tk/lib/tk/menubar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/menubar.rb
 #
diff --git a/ext/tk/lib/tk/menuspec.rb b/ext/tk/lib/tk/menuspec.rb
index cb3597eec9..2de62242ff 100644
--- a/ext/tk/lib/tk/menuspec.rb
+++ b/ext/tk/lib/tk/menuspec.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/menuspec.rb
 #                              Hidethoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tk/message.rb b/ext/tk/lib/tk/message.rb
index 5f73b3066f..432e9667bd 100644
--- a/ext/tk/lib/tk/message.rb
+++ b/ext/tk/lib/tk/message.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/message.rb : treat message widget
 #
diff --git a/ext/tk/lib/tk/mngfocus.rb b/ext/tk/lib/tk/mngfocus.rb
index a05fb94f8e..06b20eb6ab 100644
--- a/ext/tk/lib/tk/mngfocus.rb
+++ b/ext/tk/lib/tk/mngfocus.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tk/mngfocus.rb : methods for Tcl/Tk standard library 'focus.tcl'
 #                           by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/msgcat.rb b/ext/tk/lib/tk/msgcat.rb
index f2d0653c69..1e98889faf 100644
--- a/ext/tk/lib/tk/msgcat.rb
+++ b/ext/tk/lib/tk/msgcat.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tk/msgcat.rb : methods for Tcl message catalog
 #                     by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/namespace.rb b/ext/tk/lib/tk/namespace.rb
index 0119ba5ef7..1cab6fa060 100644
--- a/ext/tk/lib/tk/namespace.rb
+++ b/ext/tk/lib/tk/namespace.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tk/namespace.rb : methods to manipulate Tcl/Tk namespace
 #                           by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/optiondb.rb b/ext/tk/lib/tk/optiondb.rb
index 91d2697a86..b27a5e5721 100644
--- a/ext/tk/lib/tk/optiondb.rb
+++ b/ext/tk/lib/tk/optiondb.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/optiondb.rb : treat option database
 #
diff --git a/ext/tk/lib/tk/optionobj.rb b/ext/tk/lib/tk/optionobj.rb
index 29b06da0eb..4219e4be71 100644
--- a/ext/tk/lib/tk/optionobj.rb
+++ b/ext/tk/lib/tk/optionobj.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/optionobj.rb : control options for a group of widgets
 #
diff --git a/ext/tk/lib/tk/pack.rb b/ext/tk/lib/tk/pack.rb
index 220a38e524..45926d4043 100644
--- a/ext/tk/lib/tk/pack.rb
+++ b/ext/tk/lib/tk/pack.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/pack.rb : control pack geometry manager
 #
diff --git a/ext/tk/lib/tk/package.rb b/ext/tk/lib/tk/package.rb
index 0c329732f5..fe6939c2d4 100644
--- a/ext/tk/lib/tk/package.rb
+++ b/ext/tk/lib/tk/package.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/package.rb : package command
 #
diff --git a/ext/tk/lib/tk/palette.rb b/ext/tk/lib/tk/palette.rb
index 9462bb0667..e118e8dbe5 100644
--- a/ext/tk/lib/tk/palette.rb
+++ b/ext/tk/lib/tk/palette.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tk/palette.rb : methods for Tcl/Tk standard library 'palette.tcl'
 #                     1998/06/21 by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/panedwindow.rb b/ext/tk/lib/tk/panedwindow.rb
index 04407802ea..285292f018 100644
--- a/ext/tk/lib/tk/panedwindow.rb
+++ b/ext/tk/lib/tk/panedwindow.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/panedwindow.rb : treat panedwindow
 #
diff --git a/ext/tk/lib/tk/place.rb b/ext/tk/lib/tk/place.rb
index 109d866fda..efda36df5e 100644
--- a/ext/tk/lib/tk/place.rb
+++ b/ext/tk/lib/tk/place.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/place.rb : control place geometry manager
 #
diff --git a/ext/tk/lib/tk/radiobutton.rb b/ext/tk/lib/tk/radiobutton.rb
index 627df6d9cf..b0858df2b4 100644
--- a/ext/tk/lib/tk/radiobutton.rb
+++ b/ext/tk/lib/tk/radiobutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/radiobutton.rb : treat radiobutton widget
 #
diff --git a/ext/tk/lib/tk/root.rb b/ext/tk/lib/tk/root.rb
index b4f0bd107f..3fb7c472d3 100644
--- a/ext/tk/lib/tk/root.rb
+++ b/ext/tk/lib/tk/root.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/root.rb : treat root widget
 #
diff --git a/ext/tk/lib/tk/scale.rb b/ext/tk/lib/tk/scale.rb
index 0bdcead7f2..f6f60e3c25 100644
--- a/ext/tk/lib/tk/scale.rb
+++ b/ext/tk/lib/tk/scale.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/scale.rb : treat scale widget
 #
diff --git a/ext/tk/lib/tk/scrollable.rb b/ext/tk/lib/tk/scrollable.rb
index 96959b7a4b..e9b4a93d6d 100644
--- a/ext/tk/lib/tk/scrollable.rb
+++ b/ext/tk/lib/tk/scrollable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/scrollable.rb : module for scrollable widget
 #
diff --git a/ext/tk/lib/tk/scrollbar.rb b/ext/tk/lib/tk/scrollbar.rb
index c0ac201acb..c16ed38756 100644
--- a/ext/tk/lib/tk/scrollbar.rb
+++ b/ext/tk/lib/tk/scrollbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/scrollbar.rb : treat scrollbar widget
 #
diff --git a/ext/tk/lib/tk/scrollbox.rb b/ext/tk/lib/tk/scrollbox.rb
index d20742a666..a470765d7c 100644
--- a/ext/tk/lib/tk/scrollbox.rb
+++ b/ext/tk/lib/tk/scrollbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #               tk/scrollbox.rb - Tk Listbox with Scrollbar
 #                                 as an example of Composite Widget
diff --git a/ext/tk/lib/tk/selection.rb b/ext/tk/lib/tk/selection.rb
index ba0a6f49f9..085d8b2d2d 100644
--- a/ext/tk/lib/tk/selection.rb
+++ b/ext/tk/lib/tk/selection.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/selection.rb : control selection
 #
diff --git a/ext/tk/lib/tk/spinbox.rb b/ext/tk/lib/tk/spinbox.rb
index f2917d60ca..4be41c4266 100644
--- a/ext/tk/lib/tk/spinbox.rb
+++ b/ext/tk/lib/tk/spinbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #               tk/spinbox.rb - Tk spinbox classes
 #                       by Yukihiro Matsumoto <matz@caelum.co.jp>
diff --git a/ext/tk/lib/tk/tagfont.rb b/ext/tk/lib/tk/tagfont.rb
index a1807395d2..e3fd60465c 100644
--- a/ext/tk/lib/tk/tagfont.rb
+++ b/ext/tk/lib/tk/tagfont.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/tagfont.rb : control font of tags
 #
diff --git a/ext/tk/lib/tk/text.rb b/ext/tk/lib/tk/text.rb
index c18b3843b4..fc4f112933 100644
--- a/ext/tk/lib/tk/text.rb
+++ b/ext/tk/lib/tk/text.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #               tk/text.rb - Tk text classes
 #                       by Yukihiro Matsumoto <matz@caelum.co.jp>
diff --git a/ext/tk/lib/tk/textimage.rb b/ext/tk/lib/tk/textimage.rb
index 99027a06fb..f7329c5dcc 100644
--- a/ext/tk/lib/tk/textimage.rb
+++ b/ext/tk/lib/tk/textimage.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/textimage.rb - treat Tk text image object
 #
diff --git a/ext/tk/lib/tk/textmark.rb b/ext/tk/lib/tk/textmark.rb
index d1888c5e54..80945cc70c 100644
--- a/ext/tk/lib/tk/textmark.rb
+++ b/ext/tk/lib/tk/textmark.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/textmark.rb - methods for treating text marks
 #
diff --git a/ext/tk/lib/tk/texttag.rb b/ext/tk/lib/tk/texttag.rb
index 96692014e4..9f11c6539b 100644
--- a/ext/tk/lib/tk/texttag.rb
+++ b/ext/tk/lib/tk/texttag.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/texttag.rb - methods for treating text tags
 #
diff --git a/ext/tk/lib/tk/textwindow.rb b/ext/tk/lib/tk/textwindow.rb
index 49327b2c81..e0be5bac7a 100644
--- a/ext/tk/lib/tk/textwindow.rb
+++ b/ext/tk/lib/tk/textwindow.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/textwindow.rb - treat Tk text window object
 #
diff --git a/ext/tk/lib/tk/timer.rb b/ext/tk/lib/tk/timer.rb
index 29aa84b0d9..794463aab1 100644
--- a/ext/tk/lib/tk/timer.rb
+++ b/ext/tk/lib/tk/timer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tk/timer.rb : methods for Tcl/Tk after command
 #
diff --git a/ext/tk/lib/tk/tk_mac.rb b/ext/tk/lib/tk/tk_mac.rb
index 77bb2349cc..ed90fd1c67 100644
--- a/ext/tk/lib/tk/tk_mac.rb
+++ b/ext/tk/lib/tk/tk_mac.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/tk_mac.rb : Access Mac-Specific functionality on OS X from Tk
 #                (supported by Tk8.6 or later)
diff --git a/ext/tk/lib/tk/toplevel.rb b/ext/tk/lib/tk/toplevel.rb
index 30ef009517..e66b0fc1be 100644
--- a/ext/tk/lib/tk/toplevel.rb
+++ b/ext/tk/lib/tk/toplevel.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/toplevel.rb : treat toplevel widget
 #
diff --git a/ext/tk/lib/tk/ttk_selector.rb b/ext/tk/lib/tk/ttk_selector.rb
index cc9e9928cb..4589e7fc29 100644
--- a/ext/tk/lib/tk/ttk_selector.rb
+++ b/ext/tk/lib/tk/ttk_selector.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  ttk_selector
 #
diff --git a/ext/tk/lib/tk/txtwin_abst.rb b/ext/tk/lib/tk/txtwin_abst.rb
index 540f806d17..3c9beef6c4 100644
--- a/ext/tk/lib/tk/txtwin_abst.rb
+++ b/ext/tk/lib/tk/txtwin_abst.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/txtwin_abst.rb : TkTextWin abstruct class
 #
diff --git a/ext/tk/lib/tk/validation.rb b/ext/tk/lib/tk/validation.rb
index 0ebd5c51b7..c6cbfb280e 100644
--- a/ext/tk/lib/tk/validation.rb
+++ b/ext/tk/lib/tk/validation.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tk/validation.rb - validation support module for entry, spinbox, and so on
 #
diff --git a/ext/tk/lib/tk/variable.rb b/ext/tk/lib/tk/variable.rb
index 496225a92d..8ac0fc6ace 100644
--- a/ext/tk/lib/tk/variable.rb
+++ b/ext/tk/lib/tk/variable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/variable.rb : treat Tk variable object
 #
diff --git a/ext/tk/lib/tk/virtevent.rb b/ext/tk/lib/tk/virtevent.rb
index c11e9692e7..de3c33da36 100644
--- a/ext/tk/lib/tk/virtevent.rb
+++ b/ext/tk/lib/tk/virtevent.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tk/virtevent.rb : treats virtual events
 #                     1998/07/16 by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/winfo.rb b/ext/tk/lib/tk/winfo.rb
index b10cfe6760..36f32e5952 100644
--- a/ext/tk/lib/tk/winfo.rb
+++ b/ext/tk/lib/tk/winfo.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/winfo.rb : methods for winfo command
 #
diff --git a/ext/tk/lib/tk/winpkg.rb b/ext/tk/lib/tk/winpkg.rb
index 80e0439ace..2a8f724bef 100644
--- a/ext/tk/lib/tk/winpkg.rb
+++ b/ext/tk/lib/tk/winpkg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tk/winpkg.rb : methods for Tcl/Tk packages for Microsoft Windows
 #                     2000/11/22 by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/wm.rb b/ext/tk/lib/tk/wm.rb
index fcd5a2cbd2..114ba24276 100644
--- a/ext/tk/lib/tk/wm.rb
+++ b/ext/tk/lib/tk/wm.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/wm.rb : methods for wm command
 #
diff --git a/ext/tk/lib/tk/xim.rb b/ext/tk/lib/tk/xim.rb
index c0126c5175..7e77591b45 100644
--- a/ext/tk/lib/tk/xim.rb
+++ b/ext/tk/lib/tk/xim.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # tk/xim.rb : control imput_method
 #
diff --git a/ext/tk/lib/tkafter.rb b/ext/tk/lib/tkafter.rb
index f65945884c..0ce5049d4a 100644
--- a/ext/tk/lib/tkafter.rb
+++ b/ext/tk/lib/tkafter.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tkafter.rb - load tk/after.rb
 #
diff --git a/ext/tk/lib/tkbgerror.rb b/ext/tk/lib/tkbgerror.rb
index deba7a57fa..875f3fef2f 100644
--- a/ext/tk/lib/tkbgerror.rb
+++ b/ext/tk/lib/tkbgerror.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tkbgerror.rb - load tk/bgerror.rb
 #
diff --git a/ext/tk/lib/tkcanvas.rb b/ext/tk/lib/tkcanvas.rb
index 9524614291..d4d0afac9e 100644
--- a/ext/tk/lib/tkcanvas.rb
+++ b/ext/tk/lib/tkcanvas.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tkcanvas.rb - load tk/canvas.rb
 #
diff --git a/ext/tk/lib/tkclass.rb b/ext/tk/lib/tkclass.rb
index 87f5acc453..947cbf3a4a 100644
--- a/ext/tk/lib/tkclass.rb
+++ b/ext/tk/lib/tkclass.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #               tkclass.rb - Tk classes
 #                       Date: 2000/11/27 09:23:36
diff --git a/ext/tk/lib/tkconsole.rb b/ext/tk/lib/tkconsole.rb
index 9960ddb8ac..f4e8669c11 100644
--- a/ext/tk/lib/tkconsole.rb
+++ b/ext/tk/lib/tkconsole.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tkconsole.rb - load tk/console.rb
 #
diff --git a/ext/tk/lib/tkdialog.rb b/ext/tk/lib/tkdialog.rb
index bec5e5d29a..7a24e2a37a 100644
--- a/ext/tk/lib/tkdialog.rb
+++ b/ext/tk/lib/tkdialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tkdialog.rb - load tk/dialog.rb
 #
diff --git a/ext/tk/lib/tkentry.rb b/ext/tk/lib/tkentry.rb
index 2dcfcab5da..9ae2f7c8fe 100644
--- a/ext/tk/lib/tkentry.rb
+++ b/ext/tk/lib/tkentry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tkentry.rb - load tk/entry.rb
 #
diff --git a/ext/tk/lib/tkextlib/ICONS.rb b/ext/tk/lib/tkextlib/ICONS.rb
index 18d84c05e9..10402c1292 100644
--- a/ext/tk/lib/tkextlib/ICONS.rb
+++ b/ext/tk/lib/tkextlib/ICONS.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  ICONS support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/ICONS/icons.rb b/ext/tk/lib/tkextlib/ICONS/icons.rb
index bd3180aa55..2934757b6d 100644
--- a/ext/tk/lib/tkextlib/ICONS/icons.rb
+++ b/ext/tk/lib/tkextlib/ICONS/icons.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/ICONS/icons.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/ICONS/setup.rb b/ext/tk/lib/tkextlib/ICONS/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/ICONS/setup.rb
+++ b/ext/tk/lib/tkextlib/ICONS/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/blt.rb b/ext/tk/lib/tkextlib/blt.rb
index 8b132e41a7..665e41226f 100644
--- a/ext/tk/lib/tkextlib/blt.rb
+++ b/ext/tk/lib/tkextlib/blt.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  BLT support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/barchart.rb b/ext/tk/lib/tkextlib/blt/barchart.rb
index a86b91c959..5b6f09ead3 100644
--- a/ext/tk/lib/tkextlib/blt/barchart.rb
+++ b/ext/tk/lib/tkextlib/blt/barchart.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/barchart.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/bitmap.rb b/ext/tk/lib/tkextlib/blt/bitmap.rb
index 3254b63116..b9f411044e 100644
--- a/ext/tk/lib/tkextlib/blt/bitmap.rb
+++ b/ext/tk/lib/tkextlib/blt/bitmap.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/bitmap.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/busy.rb b/ext/tk/lib/tkextlib/blt/busy.rb
index b5287fb5b7..ab24420750 100644
--- a/ext/tk/lib/tkextlib/blt/busy.rb
+++ b/ext/tk/lib/tkextlib/blt/busy.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/busy.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/component.rb b/ext/tk/lib/tkextlib/blt/component.rb
index c7ea213cee..a6b6f13905 100644
--- a/ext/tk/lib/tkextlib/blt/component.rb
+++ b/ext/tk/lib/tkextlib/blt/component.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/component.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/container.rb b/ext/tk/lib/tkextlib/blt/container.rb
index be05828d95..6ee11138d7 100644
--- a/ext/tk/lib/tkextlib/blt/container.rb
+++ b/ext/tk/lib/tkextlib/blt/container.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/container.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/cutbuffer.rb b/ext/tk/lib/tkextlib/blt/cutbuffer.rb
index 1cc39dfb94..b36aece6e7 100644
--- a/ext/tk/lib/tkextlib/blt/cutbuffer.rb
+++ b/ext/tk/lib/tkextlib/blt/cutbuffer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/cutbuffer.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/dragdrop.rb b/ext/tk/lib/tkextlib/blt/dragdrop.rb
index aa5c5654c2..dc2531b12e 100644
--- a/ext/tk/lib/tkextlib/blt/dragdrop.rb
+++ b/ext/tk/lib/tkextlib/blt/dragdrop.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/dragdrop.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/eps.rb b/ext/tk/lib/tkextlib/blt/eps.rb
index 0dba87a7cc..bd2d3cc47e 100644
--- a/ext/tk/lib/tkextlib/blt/eps.rb
+++ b/ext/tk/lib/tkextlib/blt/eps.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/eps.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/graph.rb b/ext/tk/lib/tkextlib/blt/graph.rb
index 6bd4424065..02de006f33 100644
--- a/ext/tk/lib/tkextlib/blt/graph.rb
+++ b/ext/tk/lib/tkextlib/blt/graph.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/graph.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/htext.rb b/ext/tk/lib/tkextlib/blt/htext.rb
index 878bd9982d..d0f5e8b5e6 100644
--- a/ext/tk/lib/tkextlib/blt/htext.rb
+++ b/ext/tk/lib/tkextlib/blt/htext.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/htext.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/setup.rb b/ext/tk/lib/tkextlib/blt/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/blt/setup.rb
+++ b/ext/tk/lib/tkextlib/blt/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/blt/spline.rb b/ext/tk/lib/tkextlib/blt/spline.rb
index 9f75a0b217..84d96a08f0 100644
--- a/ext/tk/lib/tkextlib/blt/spline.rb
+++ b/ext/tk/lib/tkextlib/blt/spline.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/spline.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/stripchart.rb b/ext/tk/lib/tkextlib/blt/stripchart.rb
index 74093f1868..332521ab0b 100644
--- a/ext/tk/lib/tkextlib/blt/stripchart.rb
+++ b/ext/tk/lib/tkextlib/blt/stripchart.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/stripchart.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/table.rb b/ext/tk/lib/tkextlib/blt/table.rb
index 205e29e6c5..39e345408d 100644
--- a/ext/tk/lib/tkextlib/blt/table.rb
+++ b/ext/tk/lib/tkextlib/blt/table.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/table.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tabnotebook.rb b/ext/tk/lib/tkextlib/blt/tabnotebook.rb
index 82936c67d3..f08f198163 100644
--- a/ext/tk/lib/tkextlib/blt/tabnotebook.rb
+++ b/ext/tk/lib/tkextlib/blt/tabnotebook.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/tabnotebook.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tabset.rb b/ext/tk/lib/tkextlib/blt/tabset.rb
index c4716c7304..022d9784e9 100644
--- a/ext/tk/lib/tkextlib/blt/tabset.rb
+++ b/ext/tk/lib/tkextlib/blt/tabset.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/tabset.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/ted.rb b/ext/tk/lib/tkextlib/blt/ted.rb
index 53ab9acdaa..7e81eab27d 100644
--- a/ext/tk/lib/tkextlib/blt/ted.rb
+++ b/ext/tk/lib/tkextlib/blt/ted.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/ted.rb
 #
diff --git a/ext/tk/lib/tkextlib/blt/tile.rb b/ext/tk/lib/tkextlib/blt/tile.rb
index c67cafd8d6..f52a5d3944 100644
--- a/ext/tk/lib/tkextlib/blt/tile.rb
+++ b/ext/tk/lib/tkextlib/blt/tile.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/tile.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tile/button.rb b/ext/tk/lib/tkextlib/blt/tile/button.rb
index 2e0863cfbe..e3d819edb7 100644
--- a/ext/tk/lib/tkextlib/blt/tile/button.rb
+++ b/ext/tk/lib/tkextlib/blt/tile/button.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/tile/button.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tile/checkbutton.rb b/ext/tk/lib/tkextlib/blt/tile/checkbutton.rb
index da230b5925..0c8c7f9774 100644
--- a/ext/tk/lib/tkextlib/blt/tile/checkbutton.rb
+++ b/ext/tk/lib/tkextlib/blt/tile/checkbutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/tile/checkbutton.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tile/frame.rb b/ext/tk/lib/tkextlib/blt/tile/frame.rb
index 5434af4b72..8d979fe485 100644
--- a/ext/tk/lib/tkextlib/blt/tile/frame.rb
+++ b/ext/tk/lib/tkextlib/blt/tile/frame.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/tile/frame.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tile/label.rb b/ext/tk/lib/tkextlib/blt/tile/label.rb
index f370c1403b..f58450d902 100644
--- a/ext/tk/lib/tkextlib/blt/tile/label.rb
+++ b/ext/tk/lib/tkextlib/blt/tile/label.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/tile/label.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tile/radiobutton.rb b/ext/tk/lib/tkextlib/blt/tile/radiobutton.rb
index 814f9a5cc4..ee449c75b0 100644
--- a/ext/tk/lib/tkextlib/blt/tile/radiobutton.rb
+++ b/ext/tk/lib/tkextlib/blt/tile/radiobutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/tile/radiobutton.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tile/scrollbar.rb b/ext/tk/lib/tkextlib/blt/tile/scrollbar.rb
index 2ae871d518..35d878d5aa 100644
--- a/ext/tk/lib/tkextlib/blt/tile/scrollbar.rb
+++ b/ext/tk/lib/tkextlib/blt/tile/scrollbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/tile/scrollbar.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tile/toplevel.rb b/ext/tk/lib/tkextlib/blt/tile/toplevel.rb
index 76d5f86b1b..e30b8b37b5 100644
--- a/ext/tk/lib/tkextlib/blt/tile/toplevel.rb
+++ b/ext/tk/lib/tkextlib/blt/tile/toplevel.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/tile/toplevel.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tree.rb b/ext/tk/lib/tkextlib/blt/tree.rb
index 1a3563e60d..6c84ef78a6 100644
--- a/ext/tk/lib/tkextlib/blt/tree.rb
+++ b/ext/tk/lib/tkextlib/blt/tree.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/tree.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/treeview.rb b/ext/tk/lib/tkextlib/blt/treeview.rb
index 38d90412e0..2866ba3027 100644
--- a/ext/tk/lib/tkextlib/blt/treeview.rb
+++ b/ext/tk/lib/tkextlib/blt/treeview.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/treeview.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/unix_dnd.rb b/ext/tk/lib/tkextlib/blt/unix_dnd.rb
index 8996f7c891..3c0cd33b79 100644
--- a/ext/tk/lib/tkextlib/blt/unix_dnd.rb
+++ b/ext/tk/lib/tkextlib/blt/unix_dnd.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/unix_dnd.rb
 #
diff --git a/ext/tk/lib/tkextlib/blt/vector.rb b/ext/tk/lib/tkextlib/blt/vector.rb
index 742e901d3e..a3ab7e64b2 100644
--- a/ext/tk/lib/tkextlib/blt/vector.rb
+++ b/ext/tk/lib/tkextlib/blt/vector.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/vector.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/watch.rb b/ext/tk/lib/tkextlib/blt/watch.rb
index 292623ff58..b88c81c745 100644
--- a/ext/tk/lib/tkextlib/blt/watch.rb
+++ b/ext/tk/lib/tkextlib/blt/watch.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/watch.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/win_printer.rb b/ext/tk/lib/tkextlib/blt/win_printer.rb
index 7ac6a0dcfc..8d609acc19 100644
--- a/ext/tk/lib/tkextlib/blt/win_printer.rb
+++ b/ext/tk/lib/tkextlib/blt/win_printer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/win_printer.rb
 #
diff --git a/ext/tk/lib/tkextlib/blt/winop.rb b/ext/tk/lib/tkextlib/blt/winop.rb
index 03bdb60810..38033e1113 100644
--- a/ext/tk/lib/tkextlib/blt/winop.rb
+++ b/ext/tk/lib/tkextlib/blt/winop.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/blt/winop.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget.rb b/ext/tk/lib/tkextlib/bwidget.rb
index 7a1eff51d8..0fa9c77ecf 100644
--- a/ext/tk/lib/tkextlib/bwidget.rb
+++ b/ext/tk/lib/tkextlib/bwidget.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  BWidget extension support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/arrowbutton.rb b/ext/tk/lib/tkextlib/bwidget/arrowbutton.rb
index 13fe9e59bf..a991245065 100644
--- a/ext/tk/lib/tkextlib/bwidget/arrowbutton.rb
+++ b/ext/tk/lib/tkextlib/bwidget/arrowbutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/arrowbutton.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/bitmap.rb b/ext/tk/lib/tkextlib/bwidget/bitmap.rb
index 6cfde203e8..3acdfdf5ec 100644
--- a/ext/tk/lib/tkextlib/bwidget/bitmap.rb
+++ b/ext/tk/lib/tkextlib/bwidget/bitmap.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/bitmap.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/button.rb b/ext/tk/lib/tkextlib/bwidget/button.rb
index e139fb6708..ad880ebfdd 100644
--- a/ext/tk/lib/tkextlib/bwidget/button.rb
+++ b/ext/tk/lib/tkextlib/bwidget/button.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/button.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/buttonbox.rb b/ext/tk/lib/tkextlib/bwidget/buttonbox.rb
index a6de33c40c..780a6a649e 100644
--- a/ext/tk/lib/tkextlib/bwidget/buttonbox.rb
+++ b/ext/tk/lib/tkextlib/bwidget/buttonbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/buttonbox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/combobox.rb b/ext/tk/lib/tkextlib/bwidget/combobox.rb
index 16143dfbc6..b3de3186d6 100644
--- a/ext/tk/lib/tkextlib/bwidget/combobox.rb
+++ b/ext/tk/lib/tkextlib/bwidget/combobox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/combobox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/dialog.rb b/ext/tk/lib/tkextlib/bwidget/dialog.rb
index 3b0656f021..ed929cb830 100644
--- a/ext/tk/lib/tkextlib/bwidget/dialog.rb
+++ b/ext/tk/lib/tkextlib/bwidget/dialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/dialog.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/dragsite.rb b/ext/tk/lib/tkextlib/bwidget/dragsite.rb
index 4d4de1780c..6c7ea4491a 100644
--- a/ext/tk/lib/tkextlib/bwidget/dragsite.rb
+++ b/ext/tk/lib/tkextlib/bwidget/dragsite.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/dragsite.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/dropsite.rb b/ext/tk/lib/tkextlib/bwidget/dropsite.rb
index e5e98fbc51..e5eb7f4a88 100644
--- a/ext/tk/lib/tkextlib/bwidget/dropsite.rb
+++ b/ext/tk/lib/tkextlib/bwidget/dropsite.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/dropsite.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/dynamichelp.rb b/ext/tk/lib/tkextlib/bwidget/dynamichelp.rb
index 846e58062d..7e7538fc00 100644
--- a/ext/tk/lib/tkextlib/bwidget/dynamichelp.rb
+++ b/ext/tk/lib/tkextlib/bwidget/dynamichelp.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/dynamichelp.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/entry.rb b/ext/tk/lib/tkextlib/bwidget/entry.rb
index 8dc4496123..bfbe2f1967 100644
--- a/ext/tk/lib/tkextlib/bwidget/entry.rb
+++ b/ext/tk/lib/tkextlib/bwidget/entry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/entry.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/label.rb b/ext/tk/lib/tkextlib/bwidget/label.rb
index e8d9352c62..9a0b73d95c 100644
--- a/ext/tk/lib/tkextlib/bwidget/label.rb
+++ b/ext/tk/lib/tkextlib/bwidget/label.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/label.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/labelentry.rb b/ext/tk/lib/tkextlib/bwidget/labelentry.rb
index 16e7b46933..501f9515fa 100644
--- a/ext/tk/lib/tkextlib/bwidget/labelentry.rb
+++ b/ext/tk/lib/tkextlib/bwidget/labelentry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/labelentry.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/labelframe.rb b/ext/tk/lib/tkextlib/bwidget/labelframe.rb
index 0710f213f0..21c529c6c9 100644
--- a/ext/tk/lib/tkextlib/bwidget/labelframe.rb
+++ b/ext/tk/lib/tkextlib/bwidget/labelframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/labelframe.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/listbox.rb b/ext/tk/lib/tkextlib/bwidget/listbox.rb
index 930491c869..394c379a34 100644
--- a/ext/tk/lib/tkextlib/bwidget/listbox.rb
+++ b/ext/tk/lib/tkextlib/bwidget/listbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/listbox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/mainframe.rb b/ext/tk/lib/tkextlib/bwidget/mainframe.rb
index 92253bd8d3..ad097439c3 100644
--- a/ext/tk/lib/tkextlib/bwidget/mainframe.rb
+++ b/ext/tk/lib/tkextlib/bwidget/mainframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/mainframe.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/messagedlg.rb b/ext/tk/lib/tkextlib/bwidget/messagedlg.rb
index 7b62614737..69819360a8 100644
--- a/ext/tk/lib/tkextlib/bwidget/messagedlg.rb
+++ b/ext/tk/lib/tkextlib/bwidget/messagedlg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/messagedlg.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/notebook.rb b/ext/tk/lib/tkextlib/bwidget/notebook.rb
index ed28bcd86a..05c8939a30 100644
--- a/ext/tk/lib/tkextlib/bwidget/notebook.rb
+++ b/ext/tk/lib/tkextlib/bwidget/notebook.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/notebook.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/pagesmanager.rb b/ext/tk/lib/tkextlib/bwidget/pagesmanager.rb
index 31bbf1fb8b..ce18ee0edb 100644
--- a/ext/tk/lib/tkextlib/bwidget/pagesmanager.rb
+++ b/ext/tk/lib/tkextlib/bwidget/pagesmanager.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/pagesmanager.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/panedwindow.rb b/ext/tk/lib/tkextlib/bwidget/panedwindow.rb
index 54cf06cbde..560c563479 100644
--- a/ext/tk/lib/tkextlib/bwidget/panedwindow.rb
+++ b/ext/tk/lib/tkextlib/bwidget/panedwindow.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/panedwindow.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/panelframe.rb b/ext/tk/lib/tkextlib/bwidget/panelframe.rb
index 1cbf914425..0e32f4e261 100644
--- a/ext/tk/lib/tkextlib/bwidget/panelframe.rb
+++ b/ext/tk/lib/tkextlib/bwidget/panelframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/panelframe.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/passwddlg.rb b/ext/tk/lib/tkextlib/bwidget/passwddlg.rb
index ea50c87cef..9fe6fc6a02 100644
--- a/ext/tk/lib/tkextlib/bwidget/passwddlg.rb
+++ b/ext/tk/lib/tkextlib/bwidget/passwddlg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/passwddlg.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/progressbar.rb b/ext/tk/lib/tkextlib/bwidget/progressbar.rb
index 18eb67349b..f06ddc164e 100644
--- a/ext/tk/lib/tkextlib/bwidget/progressbar.rb
+++ b/ext/tk/lib/tkextlib/bwidget/progressbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/progressbar.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/progressdlg.rb b/ext/tk/lib/tkextlib/bwidget/progressdlg.rb
index 0c0c4540bc..e11a73e88d 100644
--- a/ext/tk/lib/tkextlib/bwidget/progressdlg.rb
+++ b/ext/tk/lib/tkextlib/bwidget/progressdlg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/progressdlg.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/scrollableframe.rb b/ext/tk/lib/tkextlib/bwidget/scrollableframe.rb
index 5bd00d6870..2b184746a4 100644
--- a/ext/tk/lib/tkextlib/bwidget/scrollableframe.rb
+++ b/ext/tk/lib/tkextlib/bwidget/scrollableframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/scrollableframe.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/scrolledwindow.rb b/ext/tk/lib/tkextlib/bwidget/scrolledwindow.rb
index ea5a18cc66..9bd5e87554 100644
--- a/ext/tk/lib/tkextlib/bwidget/scrolledwindow.rb
+++ b/ext/tk/lib/tkextlib/bwidget/scrolledwindow.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/scrolledwindow.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/scrollview.rb b/ext/tk/lib/tkextlib/bwidget/scrollview.rb
index ab27bc91cf..d60fdca89e 100644
--- a/ext/tk/lib/tkextlib/bwidget/scrollview.rb
+++ b/ext/tk/lib/tkextlib/bwidget/scrollview.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/scrollview.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/selectcolor.rb b/ext/tk/lib/tkextlib/bwidget/selectcolor.rb
index 456175e87e..85809b69bd 100644
--- a/ext/tk/lib/tkextlib/bwidget/selectcolor.rb
+++ b/ext/tk/lib/tkextlib/bwidget/selectcolor.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/selectcolor.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/selectfont.rb b/ext/tk/lib/tkextlib/bwidget/selectfont.rb
index 23419cb0fa..4f67a2e239 100644
--- a/ext/tk/lib/tkextlib/bwidget/selectfont.rb
+++ b/ext/tk/lib/tkextlib/bwidget/selectfont.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/selectfont.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/separator.rb b/ext/tk/lib/tkextlib/bwidget/separator.rb
index 6d92321210..786c41c763 100644
--- a/ext/tk/lib/tkextlib/bwidget/separator.rb
+++ b/ext/tk/lib/tkextlib/bwidget/separator.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/separator.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/setup.rb b/ext/tk/lib/tkextlib/bwidget/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/bwidget/setup.rb
+++ b/ext/tk/lib/tkextlib/bwidget/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/bwidget/spinbox.rb b/ext/tk/lib/tkextlib/bwidget/spinbox.rb
index 0a45b045fb..00fe33da39 100644
--- a/ext/tk/lib/tkextlib/bwidget/spinbox.rb
+++ b/ext/tk/lib/tkextlib/bwidget/spinbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/entry.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/statusbar.rb b/ext/tk/lib/tkextlib/bwidget/statusbar.rb
index 5c5dd43fe4..28fd6fab21 100644
--- a/ext/tk/lib/tkextlib/bwidget/statusbar.rb
+++ b/ext/tk/lib/tkextlib/bwidget/statusbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/statusbar.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/titleframe.rb b/ext/tk/lib/tkextlib/bwidget/titleframe.rb
index 71879111c1..eca622399e 100644
--- a/ext/tk/lib/tkextlib/bwidget/titleframe.rb
+++ b/ext/tk/lib/tkextlib/bwidget/titleframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/titleframe.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/tree.rb b/ext/tk/lib/tkextlib/bwidget/tree.rb
index 089c482fe8..688ed5f324 100644
--- a/ext/tk/lib/tkextlib/bwidget/tree.rb
+++ b/ext/tk/lib/tkextlib/bwidget/tree.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/tree.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/widget.rb b/ext/tk/lib/tkextlib/bwidget/widget.rb
index a93364b567..ab08826b19 100644
--- a/ext/tk/lib/tkextlib/bwidget/widget.rb
+++ b/ext/tk/lib/tkextlib/bwidget/widget.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/bwidget/widget.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/itcl.rb b/ext/tk/lib/tkextlib/itcl.rb
index 1d6ecf04f2..3a67b3f651 100644
--- a/ext/tk/lib/tkextlib/itcl.rb
+++ b/ext/tk/lib/tkextlib/itcl.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  [incr Tcl] support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/itcl/incr_tcl.rb b/ext/tk/lib/tkextlib/itcl/incr_tcl.rb
index 8f6bb33abe..de1be12392 100644
--- a/ext/tk/lib/tkextlib/itcl/incr_tcl.rb
+++ b/ext/tk/lib/tkextlib/itcl/incr_tcl.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/itk/incr_tcl.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/itcl/setup.rb b/ext/tk/lib/tkextlib/itcl/setup.rb
index 70b38e4916..917b877947 100644
--- a/ext/tk/lib/tkextlib/itcl/setup.rb
+++ b/ext/tk/lib/tkextlib/itcl/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/itk.rb b/ext/tk/lib/tkextlib/itk.rb
index 7492bd3eb4..112cb789f2 100644
--- a/ext/tk/lib/tkextlib/itk.rb
+++ b/ext/tk/lib/tkextlib/itk.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  [incr Tk] support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/itk/incr_tk.rb b/ext/tk/lib/tkextlib/itk/incr_tk.rb
index 989585e33b..8c6fe1374f 100644
--- a/ext/tk/lib/tkextlib/itk/incr_tk.rb
+++ b/ext/tk/lib/tkextlib/itk/incr_tk.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/itk/incr_tk.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/itk/setup.rb b/ext/tk/lib/tkextlib/itk/setup.rb
index 544926efe0..f32d5d6a75 100644
--- a/ext/tk/lib/tkextlib/itk/setup.rb
+++ b/ext/tk/lib/tkextlib/itk/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/iwidgets.rb b/ext/tk/lib/tkextlib/iwidgets.rb
index ebd4cf7507..2ebd9d993e 100644
--- a/ext/tk/lib/tkextlib/iwidgets.rb
+++ b/ext/tk/lib/tkextlib/iwidgets.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  [incr Widgets] support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/buttonbox.rb b/ext/tk/lib/tkextlib/iwidgets/buttonbox.rb
index 91e06d1b52..0357114c83 100644
--- a/ext/tk/lib/tkextlib/iwidgets/buttonbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/buttonbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/buttonbox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/calendar.rb b/ext/tk/lib/tkextlib/iwidgets/calendar.rb
index a5478c7cc6..4cfb9203c8 100644
--- a/ext/tk/lib/tkextlib/iwidgets/calendar.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/calendar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/calendar.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/canvasprintbox.rb b/ext/tk/lib/tkextlib/iwidgets/canvasprintbox.rb
index 398eec3f1a..3fe489dc95 100644
--- a/ext/tk/lib/tkextlib/iwidgets/canvasprintbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/canvasprintbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/canvasprintbox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/canvasprintdialog.rb b/ext/tk/lib/tkextlib/iwidgets/canvasprintdialog.rb
index e64d8154ca..4b5fdf5d7c 100644
--- a/ext/tk/lib/tkextlib/iwidgets/canvasprintdialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/canvasprintdialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/canvasprintdialog.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/checkbox.rb b/ext/tk/lib/tkextlib/iwidgets/checkbox.rb
index a7476c824e..4589fe7ffa 100644
--- a/ext/tk/lib/tkextlib/iwidgets/checkbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/checkbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/checkbox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/combobox.rb b/ext/tk/lib/tkextlib/iwidgets/combobox.rb
index 82dcf25d0b..d4c05b5be5 100644
--- a/ext/tk/lib/tkextlib/iwidgets/combobox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/combobox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/combobox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/dateentry.rb b/ext/tk/lib/tkextlib/iwidgets/dateentry.rb
index 98a0051e55..e135b89ed7 100644
--- a/ext/tk/lib/tkextlib/iwidgets/dateentry.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/dateentry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/dateentry.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/datefield.rb b/ext/tk/lib/tkextlib/iwidgets/datefield.rb
index 50d5405a3b..35977e1f6d 100644
--- a/ext/tk/lib/tkextlib/iwidgets/datefield.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/datefield.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/datefield.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/dialog.rb b/ext/tk/lib/tkextlib/iwidgets/dialog.rb
index 2d554ca7b5..edefba1844 100644
--- a/ext/tk/lib/tkextlib/iwidgets/dialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/dialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/dialog.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/dialogshell.rb b/ext/tk/lib/tkextlib/iwidgets/dialogshell.rb
index e880594532..009fc61c56 100644
--- a/ext/tk/lib/tkextlib/iwidgets/dialogshell.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/dialogshell.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/dialogshell.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/disjointlistbox.rb b/ext/tk/lib/tkextlib/iwidgets/disjointlistbox.rb
index 07ab025cdf..3ae3f319b6 100644
--- a/ext/tk/lib/tkextlib/iwidgets/disjointlistbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/disjointlistbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/disjointlistbox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/entryfield.rb b/ext/tk/lib/tkextlib/iwidgets/entryfield.rb
index 3e7149a662..75baca05d4 100644
--- a/ext/tk/lib/tkextlib/iwidgets/entryfield.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/entryfield.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/entryfield.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/extbutton.rb b/ext/tk/lib/tkextlib/iwidgets/extbutton.rb
index e744fba91a..3c77c2ec21 100644
--- a/ext/tk/lib/tkextlib/iwidgets/extbutton.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/extbutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/extbutton.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/extfileselectionbox.rb b/ext/tk/lib/tkextlib/iwidgets/extfileselectionbox.rb
index 2ff15bb509..4581771309 100644
--- a/ext/tk/lib/tkextlib/iwidgets/extfileselectionbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/extfileselectionbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/extfileselectionbox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/extfileselectiondialog.rb b/ext/tk/lib/tkextlib/iwidgets/extfileselectiondialog.rb
index 509fdcf636..32a06cc46f 100644
--- a/ext/tk/lib/tkextlib/iwidgets/extfileselectiondialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/extfileselectiondialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/extfileselectiondialog.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/feedback.rb b/ext/tk/lib/tkextlib/iwidgets/feedback.rb
index 29d04c8a5d..e52d60edac 100644
--- a/ext/tk/lib/tkextlib/iwidgets/feedback.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/feedback.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/feedback.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/fileselectionbox.rb b/ext/tk/lib/tkextlib/iwidgets/fileselectionbox.rb
index a425b53b5f..3811f2b57e 100644
--- a/ext/tk/lib/tkextlib/iwidgets/fileselectionbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/fileselectionbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/fileselectionbox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/fileselectiondialog.rb b/ext/tk/lib/tkextlib/iwidgets/fileselectiondialog.rb
index ebcdaf8c0b..8d368486ea 100644
--- a/ext/tk/lib/tkextlib/iwidgets/fileselectiondialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/fileselectiondialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/fileselectiondialog.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/finddialog.rb b/ext/tk/lib/tkextlib/iwidgets/finddialog.rb
index 3d522e07c8..ff0b587390 100644
--- a/ext/tk/lib/tkextlib/iwidgets/finddialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/finddialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/finddialog.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/hierarchy.rb b/ext/tk/lib/tkextlib/iwidgets/hierarchy.rb
index cb9301d0c9..af99973240 100644
--- a/ext/tk/lib/tkextlib/iwidgets/hierarchy.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/hierarchy.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/hierarchy.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/hyperhelp.rb b/ext/tk/lib/tkextlib/iwidgets/hyperhelp.rb
index d4ea1aac65..1650c7af37 100644
--- a/ext/tk/lib/tkextlib/iwidgets/hyperhelp.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/hyperhelp.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/hyperhelp.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/labeledframe.rb b/ext/tk/lib/tkextlib/iwidgets/labeledframe.rb
index 6595398427..f4f3786528 100644
--- a/ext/tk/lib/tkextlib/iwidgets/labeledframe.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/labeledframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/labeledframe.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/labeledwidget.rb b/ext/tk/lib/tkextlib/iwidgets/labeledwidget.rb
index d36d42878d..fe3c03135c 100644
--- a/ext/tk/lib/tkextlib/iwidgets/labeledwidget.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/labeledwidget.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/labeledwidget.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/mainwindow.rb b/ext/tk/lib/tkextlib/iwidgets/mainwindow.rb
index ebf48021db..34c9eb52e3 100644
--- a/ext/tk/lib/tkextlib/iwidgets/mainwindow.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/mainwindow.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/mainwindow.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/menubar.rb b/ext/tk/lib/tkextlib/iwidgets/menubar.rb
index f9a17d0b55..f729511230 100644
--- a/ext/tk/lib/tkextlib/iwidgets/menubar.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/menubar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/menubar.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/messagebox.rb b/ext/tk/lib/tkextlib/iwidgets/messagebox.rb
index 6adb53d941..a4c28228ee 100644
--- a/ext/tk/lib/tkextlib/iwidgets/messagebox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/messagebox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/messagebox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/messagedialog.rb b/ext/tk/lib/tkextlib/iwidgets/messagedialog.rb
index 9aa590056f..2fb4533b67 100644
--- a/ext/tk/lib/tkextlib/iwidgets/messagedialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/messagedialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/messagedialog.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/notebook.rb b/ext/tk/lib/tkextlib/iwidgets/notebook.rb
index 7ed4126a4d..ad2a372512 100644
--- a/ext/tk/lib/tkextlib/iwidgets/notebook.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/notebook.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/notebook.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/optionmenu.rb b/ext/tk/lib/tkextlib/iwidgets/optionmenu.rb
index 57a3cc7d2b..642db11ff1 100644
--- a/ext/tk/lib/tkextlib/iwidgets/optionmenu.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/optionmenu.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/optionmenu.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/panedwindow.rb b/ext/tk/lib/tkextlib/iwidgets/panedwindow.rb
index 65463cc85a..5f17bdd862 100644
--- a/ext/tk/lib/tkextlib/iwidgets/panedwindow.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/panedwindow.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/panedwindow.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/promptdialog.rb b/ext/tk/lib/tkextlib/iwidgets/promptdialog.rb
index 7c7ff7ad62..fc73a51742 100644
--- a/ext/tk/lib/tkextlib/iwidgets/promptdialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/promptdialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/promptdialog.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/pushbutton.rb b/ext/tk/lib/tkextlib/iwidgets/pushbutton.rb
index ae56788289..cec3563ddc 100644
--- a/ext/tk/lib/tkextlib/iwidgets/pushbutton.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/pushbutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/pushbutton.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/radiobox.rb b/ext/tk/lib/tkextlib/iwidgets/radiobox.rb
index 21181777b5..1c9e9f8d34 100644
--- a/ext/tk/lib/tkextlib/iwidgets/radiobox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/radiobox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/radiobox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/scopedobject.rb b/ext/tk/lib/tkextlib/iwidgets/scopedobject.rb
index 056cd85322..e17fee98dc 100644
--- a/ext/tk/lib/tkextlib/iwidgets/scopedobject.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/scopedobject.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/buttonbox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/scrolledcanvas.rb b/ext/tk/lib/tkextlib/iwidgets/scrolledcanvas.rb
index 4dea2f2d5c..463689f513 100644
--- a/ext/tk/lib/tkextlib/iwidgets/scrolledcanvas.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/scrolledcanvas.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/scrolledcanvas.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/scrolledframe.rb b/ext/tk/lib/tkextlib/iwidgets/scrolledframe.rb
index 7b7b95df1c..f105576fd6 100644
--- a/ext/tk/lib/tkextlib/iwidgets/scrolledframe.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/scrolledframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/scrolledframe.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/scrolledhtml.rb b/ext/tk/lib/tkextlib/iwidgets/scrolledhtml.rb
index dc2966bd48..4ee5abe9fc 100644
--- a/ext/tk/lib/tkextlib/iwidgets/scrolledhtml.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/scrolledhtml.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/scrolledhtml.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/scrolledlistbox.rb b/ext/tk/lib/tkextlib/iwidgets/scrolledlistbox.rb
index 20a4cd1d36..94949c5524 100644
--- a/ext/tk/lib/tkextlib/iwidgets/scrolledlistbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/scrolledlistbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/scrolledlistbox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/scrolledtext.rb b/ext/tk/lib/tkextlib/iwidgets/scrolledtext.rb
index 69b7d314fd..1e2898988c 100644
--- a/ext/tk/lib/tkextlib/iwidgets/scrolledtext.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/scrolledtext.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/scrolledtext.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/scrolledwidget.rb b/ext/tk/lib/tkextlib/iwidgets/scrolledwidget.rb
index 5ecd2d72d2..a8b4e5a27b 100644
--- a/ext/tk/lib/tkextlib/iwidgets/scrolledwidget.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/scrolledwidget.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/scrolledwidget.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/selectionbox.rb b/ext/tk/lib/tkextlib/iwidgets/selectionbox.rb
index eb8fe3ad52..333f68e306 100644
--- a/ext/tk/lib/tkextlib/iwidgets/selectionbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/selectionbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/selectionbox.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/selectiondialog.rb b/ext/tk/lib/tkextlib/iwidgets/selectiondialog.rb
index 45aecf3266..0d0b94e8d2 100644
--- a/ext/tk/lib/tkextlib/iwidgets/selectiondialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/selectiondialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/selectiondialog.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/setup.rb b/ext/tk/lib/tkextlib/iwidgets/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/iwidgets/setup.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/iwidgets/shell.rb b/ext/tk/lib/tkextlib/iwidgets/shell.rb
index c560e3ac29..f09e7d4d31 100644
--- a/ext/tk/lib/tkextlib/iwidgets/shell.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/shell.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/shell.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/spindate.rb b/ext/tk/lib/tkextlib/iwidgets/spindate.rb
index b3de9ed989..8860348cc0 100644
--- a/ext/tk/lib/tkextlib/iwidgets/spindate.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/spindate.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/spindate.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/spinint.rb b/ext/tk/lib/tkextlib/iwidgets/spinint.rb
index bede3bb1bf..85736d095c 100644
--- a/ext/tk/lib/tkextlib/iwidgets/spinint.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/spinint.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/spinint.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/spinner.rb b/ext/tk/lib/tkextlib/iwidgets/spinner.rb
index d960996e22..49968e86d8 100644
--- a/ext/tk/lib/tkextlib/iwidgets/spinner.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/spinner.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/spinner.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/spintime.rb b/ext/tk/lib/tkextlib/iwidgets/spintime.rb
index 20f8197a09..9b280ec0e4 100644
--- a/ext/tk/lib/tkextlib/iwidgets/spintime.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/spintime.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/spintime.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/tabnotebook.rb b/ext/tk/lib/tkextlib/iwidgets/tabnotebook.rb
index f56efa9aaf..89e3362185 100644
--- a/ext/tk/lib/tkextlib/iwidgets/tabnotebook.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/tabnotebook.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/tabnotebook.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/tabset.rb b/ext/tk/lib/tkextlib/iwidgets/tabset.rb
index 501ead4964..816ea087ef 100644
--- a/ext/tk/lib/tkextlib/iwidgets/tabset.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/tabset.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/tabset.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/timeentry.rb b/ext/tk/lib/tkextlib/iwidgets/timeentry.rb
index b0afb3afd9..d4078e6e4f 100644
--- a/ext/tk/lib/tkextlib/iwidgets/timeentry.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/timeentry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/timeentry.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/timefield.rb b/ext/tk/lib/tkextlib/iwidgets/timefield.rb
index c34281d4ff..d759a0762f 100644
--- a/ext/tk/lib/tkextlib/iwidgets/timefield.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/timefield.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/timefield.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/toolbar.rb b/ext/tk/lib/tkextlib/iwidgets/toolbar.rb
index 5b474c3816..7f2a54b88b 100644
--- a/ext/tk/lib/tkextlib/iwidgets/toolbar.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/toolbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/toolbar.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/watch.rb b/ext/tk/lib/tkextlib/iwidgets/watch.rb
index f10ec54cb2..c6e862b36a 100644
--- a/ext/tk/lib/tkextlib/iwidgets/watch.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/watch.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/iwidgets/watch.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/pkg_checker.rb b/ext/tk/lib/tkextlib/pkg_checker.rb
index e2fd97bb6a..76a25ca629 100755
--- a/ext/tk/lib/tkextlib/pkg_checker.rb
+++ b/ext/tk/lib/tkextlib/pkg_checker.rb
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: false
 #
 #  Ruby/Tk extension library checker
 #
diff --git a/ext/tk/lib/tkextlib/setup.rb b/ext/tk/lib/tkextlib/setup.rb
index 79facc5ee3..08ad32e99b 100644
--- a/ext/tk/lib/tkextlib/setup.rb
+++ b/ext/tk/lib/tkextlib/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before using Tk extension libraries
 #
diff --git a/ext/tk/lib/tkextlib/tcllib.rb b/ext/tk/lib/tkextlib/tcllib.rb
index 2831989759..75d250cba4 100644
--- a/ext/tk/lib/tkextlib/tcllib.rb
+++ b/ext/tk/lib/tkextlib/tcllib.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tcllib extension support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/autoscroll.rb b/ext/tk/lib/tkextlib/tcllib/autoscroll.rb
index 2def59bf73..ae45b84787 100644
--- a/ext/tk/lib/tkextlib/tcllib/autoscroll.rb
+++ b/ext/tk/lib/tkextlib/tcllib/autoscroll.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/autoscroll.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/calendar.rb b/ext/tk/lib/tkextlib/tcllib/calendar.rb
index b6843df176..fa53603d91 100644
--- a/ext/tk/lib/tkextlib/tcllib/calendar.rb
+++ b/ext/tk/lib/tkextlib/tcllib/calendar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/calendar.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/canvas_sqmap.rb b/ext/tk/lib/tkextlib/tcllib/canvas_sqmap.rb
index ba87cd3aae..f3d1847d73 100644
--- a/ext/tk/lib/tkextlib/tcllib/canvas_sqmap.rb
+++ b/ext/tk/lib/tkextlib/tcllib/canvas_sqmap.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/canvas.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/canvas_zoom.rb b/ext/tk/lib/tkextlib/tcllib/canvas_zoom.rb
index f4ffb48ece..bb8b04a18b 100644
--- a/ext/tk/lib/tkextlib/tcllib/canvas_zoom.rb
+++ b/ext/tk/lib/tkextlib/tcllib/canvas_zoom.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/canvas.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/chatwidget.rb b/ext/tk/lib/tkextlib/tcllib/chatwidget.rb
index ddb0340c31..34a8ca5094 100644
--- a/ext/tk/lib/tkextlib/tcllib/chatwidget.rb
+++ b/ext/tk/lib/tkextlib/tcllib/chatwidget.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/chatwidget.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/crosshair.rb b/ext/tk/lib/tkextlib/tcllib/crosshair.rb
index 49b5361e4f..74cc0a881c 100644
--- a/ext/tk/lib/tkextlib/tcllib/crosshair.rb
+++ b/ext/tk/lib/tkextlib/tcllib/crosshair.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/crosshair.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/ctext.rb b/ext/tk/lib/tkextlib/tcllib/ctext.rb
index 308847c233..1c61ec81a6 100644
--- a/ext/tk/lib/tkextlib/tcllib/ctext.rb
+++ b/ext/tk/lib/tkextlib/tcllib/ctext.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/ctext.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/cursor.rb b/ext/tk/lib/tkextlib/tcllib/cursor.rb
index 5c47f9709b..4c93cfc063 100644
--- a/ext/tk/lib/tkextlib/tcllib/cursor.rb
+++ b/ext/tk/lib/tkextlib/tcllib/cursor.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/cursor.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/dateentry.rb b/ext/tk/lib/tkextlib/tcllib/dateentry.rb
index 77038d95bc..81b38515fc 100644
--- a/ext/tk/lib/tkextlib/tcllib/dateentry.rb
+++ b/ext/tk/lib/tkextlib/tcllib/dateentry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/dateentry.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/datefield.rb b/ext/tk/lib/tkextlib/tcllib/datefield.rb
index 4c2eae741e..ceed1260df 100644
--- a/ext/tk/lib/tkextlib/tcllib/datefield.rb
+++ b/ext/tk/lib/tkextlib/tcllib/datefield.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/datefield.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/diagrams.rb b/ext/tk/lib/tkextlib/tcllib/diagrams.rb
index d24ba9d232..7fb7b3c7ee 100644
--- a/ext/tk/lib/tkextlib/tcllib/diagrams.rb
+++ b/ext/tk/lib/tkextlib/tcllib/diagrams.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/diagrams.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/dialog.rb b/ext/tk/lib/tkextlib/tcllib/dialog.rb
index 86a0ef2269..46fd06f177 100644
--- a/ext/tk/lib/tkextlib/tcllib/dialog.rb
+++ b/ext/tk/lib/tkextlib/tcllib/dialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/dialog.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/getstring.rb b/ext/tk/lib/tkextlib/tcllib/getstring.rb
index 48711d3b66..72d9c5f517 100644
--- a/ext/tk/lib/tkextlib/tcllib/getstring.rb
+++ b/ext/tk/lib/tkextlib/tcllib/getstring.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/getstring.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/history.rb b/ext/tk/lib/tkextlib/tcllib/history.rb
index a01a4ebfcc..a1b92726ee 100644
--- a/ext/tk/lib/tkextlib/tcllib/history.rb
+++ b/ext/tk/lib/tkextlib/tcllib/history.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/history.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/ico.rb b/ext/tk/lib/tkextlib/tcllib/ico.rb
index 36a32c6b09..8814205f94 100644
--- a/ext/tk/lib/tkextlib/tcllib/ico.rb
+++ b/ext/tk/lib/tkextlib/tcllib/ico.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/ico.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/ip_entry.rb b/ext/tk/lib/tkextlib/tcllib/ip_entry.rb
index 4878cc3c23..6bbd8442a6 100644
--- a/ext/tk/lib/tkextlib/tcllib/ip_entry.rb
+++ b/ext/tk/lib/tkextlib/tcllib/ip_entry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/ip_entry.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/khim.rb b/ext/tk/lib/tkextlib/tcllib/khim.rb
index 5dc2130b35..e79f26b381 100644
--- a/ext/tk/lib/tkextlib/tcllib/khim.rb
+++ b/ext/tk/lib/tkextlib/tcllib/khim.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/khim.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/menuentry.rb b/ext/tk/lib/tkextlib/tcllib/menuentry.rb
index f1eb2f295c..51521499da 100644
--- a/ext/tk/lib/tkextlib/tcllib/menuentry.rb
+++ b/ext/tk/lib/tkextlib/tcllib/menuentry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/menuentry.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/ntext.rb b/ext/tk/lib/tkextlib/tcllib/ntext.rb
index 7888ed4871..2d0c208236 100644
--- a/ext/tk/lib/tkextlib/tcllib/ntext.rb
+++ b/ext/tk/lib/tkextlib/tcllib/ntext.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/ntext.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/panelframe.rb b/ext/tk/lib/tkextlib/tcllib/panelframe.rb
index 020c51cbd1..678d5d0a9a 100644
--- a/ext/tk/lib/tkextlib/tcllib/panelframe.rb
+++ b/ext/tk/lib/tkextlib/tcllib/panelframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/panelframe.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/plotchart.rb b/ext/tk/lib/tkextlib/tcllib/plotchart.rb
index a1ebe86692..1817f9a791 100644
--- a/ext/tk/lib/tkextlib/tcllib/plotchart.rb
+++ b/ext/tk/lib/tkextlib/tcllib/plotchart.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/plotchart.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/ruler.rb b/ext/tk/lib/tkextlib/tcllib/ruler.rb
index d22dafa053..f57b0b0e1a 100644
--- a/ext/tk/lib/tkextlib/tcllib/ruler.rb
+++ b/ext/tk/lib/tkextlib/tcllib/ruler.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/ruler.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/screenruler.rb b/ext/tk/lib/tkextlib/tcllib/screenruler.rb
index 75fa36b66d..64dd4f4ccc 100644
--- a/ext/tk/lib/tkextlib/tcllib/screenruler.rb
+++ b/ext/tk/lib/tkextlib/tcllib/screenruler.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/screenruler.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/scrolledwindow.rb b/ext/tk/lib/tkextlib/tcllib/scrolledwindow.rb
index c9488b4686..380d301a1a 100644
--- a/ext/tk/lib/tkextlib/tcllib/scrolledwindow.rb
+++ b/ext/tk/lib/tkextlib/tcllib/scrolledwindow.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/scrolledwindow.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/scrollwin.rb b/ext/tk/lib/tkextlib/tcllib/scrollwin.rb
index c9f6062fef..f9bf127799 100644
--- a/ext/tk/lib/tkextlib/tcllib/scrollwin.rb
+++ b/ext/tk/lib/tkextlib/tcllib/scrollwin.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/scrollwin.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/setup.rb b/ext/tk/lib/tkextlib/tcllib/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/tcllib/setup.rb
+++ b/ext/tk/lib/tkextlib/tcllib/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/tcllib/statusbar.rb b/ext/tk/lib/tkextlib/tcllib/statusbar.rb
index 46a4b9d8b6..b2c8f54b94 100644
--- a/ext/tk/lib/tkextlib/tcllib/statusbar.rb
+++ b/ext/tk/lib/tkextlib/tcllib/statusbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/statusbar.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/style.rb b/ext/tk/lib/tkextlib/tcllib/style.rb
index dac6916e46..f3b66b7861 100644
--- a/ext/tk/lib/tkextlib/tcllib/style.rb
+++ b/ext/tk/lib/tkextlib/tcllib/style.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/style.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/superframe.rb b/ext/tk/lib/tkextlib/tcllib/superframe.rb
index adc9c4adbd..776ad7c166 100644
--- a/ext/tk/lib/tkextlib/tcllib/superframe.rb
+++ b/ext/tk/lib/tkextlib/tcllib/superframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/superframe.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/swaplist.rb b/ext/tk/lib/tkextlib/tcllib/swaplist.rb
index 7698640534..7eaed8dbaa 100644
--- a/ext/tk/lib/tkextlib/tcllib/swaplist.rb
+++ b/ext/tk/lib/tkextlib/tcllib/swaplist.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/swaplist.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/tablelist.rb b/ext/tk/lib/tkextlib/tcllib/tablelist.rb
index bf5ab6620a..7cfe2faf1e 100644
--- a/ext/tk/lib/tkextlib/tcllib/tablelist.rb
+++ b/ext/tk/lib/tkextlib/tcllib/tablelist.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/tablelist.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/tablelist_core.rb b/ext/tk/lib/tkextlib/tcllib/tablelist_core.rb
index 2a5c415cc7..b45f18796a 100644
--- a/ext/tk/lib/tkextlib/tcllib/tablelist_core.rb
+++ b/ext/tk/lib/tkextlib/tcllib/tablelist_core.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/tablelist_core.rb
 #
diff --git a/ext/tk/lib/tkextlib/tcllib/tablelist_tile.rb b/ext/tk/lib/tkextlib/tcllib/tablelist_tile.rb
index 0a1458415e..20488fdd48 100644
--- a/ext/tk/lib/tkextlib/tcllib/tablelist_tile.rb
+++ b/ext/tk/lib/tkextlib/tcllib/tablelist_tile.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/tablelist_tlie.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/tkpiechart.rb b/ext/tk/lib/tkextlib/tcllib/tkpiechart.rb
index 2f6e4b44fc..2fc75a68ec 100644
--- a/ext/tk/lib/tkextlib/tcllib/tkpiechart.rb
+++ b/ext/tk/lib/tkextlib/tcllib/tkpiechart.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/tkpiechart.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/toolbar.rb b/ext/tk/lib/tkextlib/tcllib/toolbar.rb
index 6eae4eb3e1..ae05a16e05 100644
--- a/ext/tk/lib/tkextlib/tcllib/toolbar.rb
+++ b/ext/tk/lib/tkextlib/tcllib/toolbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/toolbar.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/tooltip.rb b/ext/tk/lib/tkextlib/tcllib/tooltip.rb
index 070e63a7b5..4a70ec5732 100644
--- a/ext/tk/lib/tkextlib/tcllib/tooltip.rb
+++ b/ext/tk/lib/tkextlib/tcllib/tooltip.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/tooltip.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/validator.rb b/ext/tk/lib/tkextlib/tcllib/validator.rb
index 3a71960afa..c2c9dda376 100644
--- a/ext/tk/lib/tkextlib/tcllib/validator.rb
+++ b/ext/tk/lib/tkextlib/tcllib/validator.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/validator.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/widget.rb b/ext/tk/lib/tkextlib/tcllib/widget.rb
index 57fdf7a575..b8d5070b0b 100644
--- a/ext/tk/lib/tkextlib/tcllib/widget.rb
+++ b/ext/tk/lib/tkextlib/tcllib/widget.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tcllib/widget.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tclx.rb b/ext/tk/lib/tkextlib/tclx.rb
index 3a4ff27644..1189d855cb 100644
--- a/ext/tk/lib/tkextlib/tclx.rb
+++ b/ext/tk/lib/tkextlib/tclx.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TclX support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tclx/setup.rb b/ext/tk/lib/tkextlib/tclx/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/tclx/setup.rb
+++ b/ext/tk/lib/tkextlib/tclx/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/tclx/tclx.rb b/ext/tk/lib/tkextlib/tclx/tclx.rb
index 5a908fcd0b..7360a85403 100644
--- a/ext/tk/lib/tkextlib/tclx/tclx.rb
+++ b/ext/tk/lib/tkextlib/tclx/tclx.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tclx/tclx.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile.rb b/ext/tk/lib/tkextlib/tile.rb
index 6c11e212ae..ef15351066 100644
--- a/ext/tk/lib/tkextlib/tile.rb
+++ b/ext/tk/lib/tkextlib/tile.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  Tile theme engin (tile widget set) support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/dialog.rb b/ext/tk/lib/tkextlib/tile/dialog.rb
index b112e6152b..d81851bb68 100644
--- a/ext/tk/lib/tkextlib/tile/dialog.rb
+++ b/ext/tk/lib/tkextlib/tile/dialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  ttk::dialog  (tile-0.7+)
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/setup.rb b/ext/tk/lib/tkextlib/tile/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/tile/setup.rb
+++ b/ext/tk/lib/tkextlib/tile/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/tile/sizegrip.rb b/ext/tk/lib/tkextlib/tile/sizegrip.rb
index 9947e0d870..4b9510aefa 100644
--- a/ext/tk/lib/tkextlib/tile/sizegrip.rb
+++ b/ext/tk/lib/tkextlib/tile/sizegrip.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  ttk::sizegrip widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/style.rb b/ext/tk/lib/tkextlib/tile/style.rb
index 83a0c9a2e8..a96cba795f 100644
--- a/ext/tk/lib/tkextlib/tile/style.rb
+++ b/ext/tk/lib/tkextlib/tile/style.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  style commands
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tbutton.rb b/ext/tk/lib/tkextlib/tile/tbutton.rb
index c852024842..217da62eca 100644
--- a/ext/tk/lib/tkextlib/tile/tbutton.rb
+++ b/ext/tk/lib/tkextlib/tile/tbutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tbutton widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tcheckbutton.rb b/ext/tk/lib/tkextlib/tile/tcheckbutton.rb
index 01751ede0f..c0e4d4b505 100644
--- a/ext/tk/lib/tkextlib/tile/tcheckbutton.rb
+++ b/ext/tk/lib/tkextlib/tile/tcheckbutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tcheckbutton widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tcombobox.rb b/ext/tk/lib/tkextlib/tile/tcombobox.rb
index b5ab827e2d..f2dec21fbf 100644
--- a/ext/tk/lib/tkextlib/tile/tcombobox.rb
+++ b/ext/tk/lib/tkextlib/tile/tcombobox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tcombobox widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tentry.rb b/ext/tk/lib/tkextlib/tile/tentry.rb
index 8d2633a774..5d577a65a6 100644
--- a/ext/tk/lib/tkextlib/tile/tentry.rb
+++ b/ext/tk/lib/tkextlib/tile/tentry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tentry widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tframe.rb b/ext/tk/lib/tkextlib/tile/tframe.rb
index d6d4312628..5ebf19d1e8 100644
--- a/ext/tk/lib/tkextlib/tile/tframe.rb
+++ b/ext/tk/lib/tkextlib/tile/tframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tframe widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tlabel.rb b/ext/tk/lib/tkextlib/tile/tlabel.rb
index 55b98acc68..3dddeafc21 100644
--- a/ext/tk/lib/tkextlib/tile/tlabel.rb
+++ b/ext/tk/lib/tkextlib/tile/tlabel.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tlabel widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tlabelframe.rb b/ext/tk/lib/tkextlib/tile/tlabelframe.rb
index a34c98583f..d512f31ffe 100644
--- a/ext/tk/lib/tkextlib/tile/tlabelframe.rb
+++ b/ext/tk/lib/tkextlib/tile/tlabelframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tlabelframe widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tmenubutton.rb b/ext/tk/lib/tkextlib/tile/tmenubutton.rb
index 1cf553ec8c..a22ebaeca7 100644
--- a/ext/tk/lib/tkextlib/tile/tmenubutton.rb
+++ b/ext/tk/lib/tkextlib/tile/tmenubutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tmenubutton widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tnotebook.rb b/ext/tk/lib/tkextlib/tile/tnotebook.rb
index 9e27e2c1fd..4089dcfd4b 100644
--- a/ext/tk/lib/tkextlib/tile/tnotebook.rb
+++ b/ext/tk/lib/tkextlib/tile/tnotebook.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tnotebook widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tpaned.rb b/ext/tk/lib/tkextlib/tile/tpaned.rb
index d6ad234559..f51a1f3b41 100644
--- a/ext/tk/lib/tkextlib/tile/tpaned.rb
+++ b/ext/tk/lib/tkextlib/tile/tpaned.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tpaned widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tprogressbar.rb b/ext/tk/lib/tkextlib/tile/tprogressbar.rb
index 0c9d15e1b9..446e053e3b 100644
--- a/ext/tk/lib/tkextlib/tile/tprogressbar.rb
+++ b/ext/tk/lib/tkextlib/tile/tprogressbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tprogressbar widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tradiobutton.rb b/ext/tk/lib/tkextlib/tile/tradiobutton.rb
index 5dbf260666..202de1eb25 100644
--- a/ext/tk/lib/tkextlib/tile/tradiobutton.rb
+++ b/ext/tk/lib/tkextlib/tile/tradiobutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tradiobutton widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/treeview.rb b/ext/tk/lib/tkextlib/tile/treeview.rb
index 85d7831671..1be8f54348 100644
--- a/ext/tk/lib/tkextlib/tile/treeview.rb
+++ b/ext/tk/lib/tkextlib/tile/treeview.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  treeview widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tscale.rb b/ext/tk/lib/tkextlib/tile/tscale.rb
index 7eefcef731..446344ecea 100644
--- a/ext/tk/lib/tkextlib/tile/tscale.rb
+++ b/ext/tk/lib/tkextlib/tile/tscale.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tscale & tprogress widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tscrollbar.rb b/ext/tk/lib/tkextlib/tile/tscrollbar.rb
index c6bba5810b..621ca48efb 100644
--- a/ext/tk/lib/tkextlib/tile/tscrollbar.rb
+++ b/ext/tk/lib/tkextlib/tile/tscrollbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tscrollbar widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tseparator.rb b/ext/tk/lib/tkextlib/tile/tseparator.rb
index ffd2f6f89f..d4a90e56db 100644
--- a/ext/tk/lib/tkextlib/tile/tseparator.rb
+++ b/ext/tk/lib/tkextlib/tile/tseparator.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tseparator widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tspinbox.rb b/ext/tk/lib/tkextlib/tile/tspinbox.rb
index 2f2d73c5ab..47d822e68c 100644
--- a/ext/tk/lib/tkextlib/tile/tspinbox.rb
+++ b/ext/tk/lib/tkextlib/tile/tspinbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  ttk::spinbox widget  (Tcl/Tk 8.6b1 or later)
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tsquare.rb b/ext/tk/lib/tkextlib/tile/tsquare.rb
index a81cd7b98a..7412966708 100644
--- a/ext/tk/lib/tkextlib/tile/tsquare.rb
+++ b/ext/tk/lib/tkextlib/tile/tsquare.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tsquare widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkDND.rb b/ext/tk/lib/tkextlib/tkDND.rb
index 5d52e34418..c76c48d169 100644
--- a/ext/tk/lib/tkextlib/tkDND.rb
+++ b/ext/tk/lib/tkextlib/tkDND.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkDND (Tk Drag & Drop Extension) support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkDND/setup.rb b/ext/tk/lib/tkextlib/tkDND/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/tkDND/setup.rb
+++ b/ext/tk/lib/tkextlib/tkDND/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/tkDND/shape.rb b/ext/tk/lib/tkextlib/tkDND/shape.rb
index d44068ed33..06d8d64ac7 100644
--- a/ext/tk/lib/tkextlib/tkDND/shape.rb
+++ b/ext/tk/lib/tkextlib/tkDND/shape.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tkDND/shape.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkDND/tkdnd.rb b/ext/tk/lib/tkextlib/tkDND/tkdnd.rb
index 38e05ce775..c2059b7c23 100644
--- a/ext/tk/lib/tkextlib/tkDND/tkdnd.rb
+++ b/ext/tk/lib/tkextlib/tkDND/tkdnd.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tkDND/tkdnd.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkHTML.rb b/ext/tk/lib/tkextlib/tkHTML.rb
index 5fddde72ff..d64e676024 100644
--- a/ext/tk/lib/tkextlib/tkHTML.rb
+++ b/ext/tk/lib/tkextlib/tkHTML.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkHtml support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkHTML/htmlwidget.rb b/ext/tk/lib/tkextlib/tkHTML/htmlwidget.rb
index b9ee90aace..362c381830 100644
--- a/ext/tk/lib/tkextlib/tkHTML/htmlwidget.rb
+++ b/ext/tk/lib/tkextlib/tkHTML/htmlwidget.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tkHTML/htmlwidget.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkHTML/setup.rb b/ext/tk/lib/tkextlib/tkHTML/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/tkHTML/setup.rb
+++ b/ext/tk/lib/tkextlib/tkHTML/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/tkimg.rb b/ext/tk/lib/tkextlib/tkimg.rb
index c01359d3ef..de4b7212c3 100644
--- a/ext/tk/lib/tkextlib/tkimg.rb
+++ b/ext/tk/lib/tkextlib/tkimg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg extension support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/bmp.rb b/ext/tk/lib/tkextlib/tkimg/bmp.rb
index ea90181aa3..48a3b7ef5f 100644
--- a/ext/tk/lib/tkextlib/tkimg/bmp.rb
+++ b/ext/tk/lib/tkextlib/tkimg/bmp.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'bmp'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/dted.rb b/ext/tk/lib/tkextlib/tkimg/dted.rb
index cae833664c..30c595c1b6 100644
--- a/ext/tk/lib/tkextlib/tkimg/dted.rb
+++ b/ext/tk/lib/tkextlib/tkimg/dted.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'DTED'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/gif.rb b/ext/tk/lib/tkextlib/tkimg/gif.rb
index d542d47561..ce5f3e94ec 100644
--- a/ext/tk/lib/tkextlib/tkimg/gif.rb
+++ b/ext/tk/lib/tkextlib/tkimg/gif.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'gif'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/ico.rb b/ext/tk/lib/tkextlib/tkimg/ico.rb
index e79bdf45e9..80656005f0 100644
--- a/ext/tk/lib/tkextlib/tkimg/ico.rb
+++ b/ext/tk/lib/tkextlib/tkimg/ico.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'ico'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/jpeg.rb b/ext/tk/lib/tkextlib/tkimg/jpeg.rb
index 2126120161..24e11a84de 100644
--- a/ext/tk/lib/tkextlib/tkimg/jpeg.rb
+++ b/ext/tk/lib/tkextlib/tkimg/jpeg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'jpeg'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/pcx.rb b/ext/tk/lib/tkextlib/tkimg/pcx.rb
index 6831f4d35b..942d585120 100644
--- a/ext/tk/lib/tkextlib/tkimg/pcx.rb
+++ b/ext/tk/lib/tkextlib/tkimg/pcx.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'pcx'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)#
diff --git a/ext/tk/lib/tkextlib/tkimg/pixmap.rb b/ext/tk/lib/tkextlib/tkimg/pixmap.rb
index bd1b870af7..b90468a108 100644
--- a/ext/tk/lib/tkextlib/tkimg/pixmap.rb
+++ b/ext/tk/lib/tkextlib/tkimg/pixmap.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'pixmap'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/png.rb b/ext/tk/lib/tkextlib/tkimg/png.rb
index 5c829f48d2..76f7329772 100644
--- a/ext/tk/lib/tkextlib/tkimg/png.rb
+++ b/ext/tk/lib/tkextlib/tkimg/png.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'png'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/ppm.rb b/ext/tk/lib/tkextlib/tkimg/ppm.rb
index eacfae467d..a6b705e6ad 100644
--- a/ext/tk/lib/tkextlib/tkimg/ppm.rb
+++ b/ext/tk/lib/tkextlib/tkimg/ppm.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'ppm'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/ps.rb b/ext/tk/lib/tkextlib/tkimg/ps.rb
index 68e9178ac0..2a450ed157 100644
--- a/ext/tk/lib/tkextlib/tkimg/ps.rb
+++ b/ext/tk/lib/tkextlib/tkimg/ps.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'ps'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/raw.rb b/ext/tk/lib/tkextlib/tkimg/raw.rb
index 5f1cdcaac0..2eddbbc43a 100644
--- a/ext/tk/lib/tkextlib/tkimg/raw.rb
+++ b/ext/tk/lib/tkextlib/tkimg/raw.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'Raw Data'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/setup.rb b/ext/tk/lib/tkextlib/tkimg/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/tkimg/setup.rb
+++ b/ext/tk/lib/tkextlib/tkimg/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/tkimg/sgi.rb b/ext/tk/lib/tkextlib/tkimg/sgi.rb
index ec7038bf0e..73a5bce0ac 100644
--- a/ext/tk/lib/tkextlib/tkimg/sgi.rb
+++ b/ext/tk/lib/tkextlib/tkimg/sgi.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'sgi'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/sun.rb b/ext/tk/lib/tkextlib/tkimg/sun.rb
index 651f946497..bd1ac0e577 100644
--- a/ext/tk/lib/tkextlib/tkimg/sun.rb
+++ b/ext/tk/lib/tkextlib/tkimg/sun.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'sun'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/tga.rb b/ext/tk/lib/tkextlib/tkimg/tga.rb
index 1eae407c0a..1dd499b953 100644
--- a/ext/tk/lib/tkextlib/tkimg/tga.rb
+++ b/ext/tk/lib/tkextlib/tkimg/tga.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'tga'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/tiff.rb b/ext/tk/lib/tkextlib/tkimg/tiff.rb
index ed271c2600..a2d1d8fcc5 100644
--- a/ext/tk/lib/tkextlib/tkimg/tiff.rb
+++ b/ext/tk/lib/tkextlib/tkimg/tiff.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'tiff'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/window.rb b/ext/tk/lib/tkextlib/tkimg/window.rb
index 3b5906fab6..346f246aa4 100644
--- a/ext/tk/lib/tkextlib/tkimg/window.rb
+++ b/ext/tk/lib/tkextlib/tkimg/window.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'window'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/xbm.rb b/ext/tk/lib/tkextlib/tkimg/xbm.rb
index f4bea030be..0a4deffdd7 100644
--- a/ext/tk/lib/tkextlib/tkimg/xbm.rb
+++ b/ext/tk/lib/tkextlib/tkimg/xbm.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'xbm'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/xpm.rb b/ext/tk/lib/tkextlib/tkimg/xpm.rb
index 5119c8710b..7708b9d427 100644
--- a/ext/tk/lib/tkextlib/tkimg/xpm.rb
+++ b/ext/tk/lib/tkextlib/tkimg/xpm.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkImg - format 'xpm'
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tktable.rb b/ext/tk/lib/tkextlib/tktable.rb
index 385eb13497..a957294db0 100644
--- a/ext/tk/lib/tkextlib/tktable.rb
+++ b/ext/tk/lib/tkextlib/tktable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkTable support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tktable/setup.rb b/ext/tk/lib/tkextlib/tktable/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/tktable/setup.rb
+++ b/ext/tk/lib/tkextlib/tktable/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/tktable/tktable.rb b/ext/tk/lib/tkextlib/tktable/tktable.rb
index f7074655ed..d8811a9676 100644
--- a/ext/tk/lib/tkextlib/tktable/tktable.rb
+++ b/ext/tk/lib/tkextlib/tktable/tktable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/tktable/tktable.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tktrans.rb b/ext/tk/lib/tkextlib/tktrans.rb
index c5de5be5e6..031eeb9fd7 100644
--- a/ext/tk/lib/tkextlib/tktrans.rb
+++ b/ext/tk/lib/tkextlib/tktrans.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkTrans support (win32 only)
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tktrans/setup.rb b/ext/tk/lib/tkextlib/tktrans/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/tktrans/setup.rb
+++ b/ext/tk/lib/tkextlib/tktrans/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/tktrans/tktrans.rb b/ext/tk/lib/tkextlib/tktrans/tktrans.rb
index e051c09211..e6e0e3a78d 100644
--- a/ext/tk/lib/tkextlib/tktrans/tktrans.rb
+++ b/ext/tk/lib/tkextlib/tktrans/tktrans.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkTrans support (win32 only)
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/treectrl.rb b/ext/tk/lib/tkextlib/treectrl.rb
index 1944fb83e3..227d55ff1e 100644
--- a/ext/tk/lib/tkextlib/treectrl.rb
+++ b/ext/tk/lib/tkextlib/treectrl.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  TkTreeCtrl support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/treectrl/setup.rb b/ext/tk/lib/tkextlib/treectrl/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/treectrl/setup.rb
+++ b/ext/tk/lib/tkextlib/treectrl/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/treectrl/tktreectrl.rb b/ext/tk/lib/tkextlib/treectrl/tktreectrl.rb
index 1879a531ae..dbd59f8c05 100644
--- a/ext/tk/lib/tkextlib/treectrl/tktreectrl.rb
+++ b/ext/tk/lib/tkextlib/treectrl/tktreectrl.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/treectrl/tktreectrl.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/trofs.rb b/ext/tk/lib/tkextlib/trofs.rb
index 5914e5165f..46581a3dad 100644
--- a/ext/tk/lib/tkextlib/trofs.rb
+++ b/ext/tk/lib/tkextlib/trofs.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  trofs support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/trofs/setup.rb b/ext/tk/lib/tkextlib/trofs/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/trofs/setup.rb
+++ b/ext/tk/lib/tkextlib/trofs/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/trofs/trofs.rb b/ext/tk/lib/tkextlib/trofs/trofs.rb
index 7a2606a275..dc55ec269a 100644
--- a/ext/tk/lib/tkextlib/trofs/trofs.rb
+++ b/ext/tk/lib/tkextlib/trofs/trofs.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/trofs/trofs.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/version.rb b/ext/tk/lib/tkextlib/version.rb
index 4bef78fe54..68c8ae31a2 100644
--- a/ext/tk/lib/tkextlib/version.rb
+++ b/ext/tk/lib/tkextlib/version.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 # release date of tkextlib
 #
diff --git a/ext/tk/lib/tkextlib/vu.rb b/ext/tk/lib/tkextlib/vu.rb
index d2234eb2a8..145a0b5647 100644
--- a/ext/tk/lib/tkextlib/vu.rb
+++ b/ext/tk/lib/tkextlib/vu.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  The vu widget set support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/vu/bargraph.rb b/ext/tk/lib/tkextlib/vu/bargraph.rb
index b9fcf925f3..e1d58e9555 100644
--- a/ext/tk/lib/tkextlib/vu/bargraph.rb
+++ b/ext/tk/lib/tkextlib/vu/bargraph.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  ::vu::bargraph widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/vu/charts.rb b/ext/tk/lib/tkextlib/vu/charts.rb
index 8569ac5541..66d5cfd394 100644
--- a/ext/tk/lib/tkextlib/vu/charts.rb
+++ b/ext/tk/lib/tkextlib/vu/charts.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  charts -- Create and manipulate canvas Add-On Items
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/vu/dial.rb b/ext/tk/lib/tkextlib/vu/dial.rb
index 4d04974a55..7eb5650df0 100644
--- a/ext/tk/lib/tkextlib/vu/dial.rb
+++ b/ext/tk/lib/tkextlib/vu/dial.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  ::vu::dial widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/vu/pie.rb b/ext/tk/lib/tkextlib/vu/pie.rb
index 6b0c485d8a..fb9920cc68 100644
--- a/ext/tk/lib/tkextlib/vu/pie.rb
+++ b/ext/tk/lib/tkextlib/vu/pie.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  ::vu::pie widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/vu/setup.rb b/ext/tk/lib/tkextlib/vu/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/vu/setup.rb
+++ b/ext/tk/lib/tkextlib/vu/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/vu/spinbox.rb b/ext/tk/lib/tkextlib/vu/spinbox.rb
index 7d6104f4d1..082ebd1f62 100644
--- a/ext/tk/lib/tkextlib/vu/spinbox.rb
+++ b/ext/tk/lib/tkextlib/vu/spinbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  ::vu::spinbox widget
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/winico.rb b/ext/tk/lib/tkextlib/winico.rb
index ce7b8eac5c..996fc409b8 100644
--- a/ext/tk/lib/tkextlib/winico.rb
+++ b/ext/tk/lib/tkextlib/winico.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  winico -- Windows Icon extension support
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/winico/setup.rb b/ext/tk/lib/tkextlib/winico/setup.rb
index ee406c6ca0..cc967dced6 100644
--- a/ext/tk/lib/tkextlib/winico/setup.rb
+++ b/ext/tk/lib/tkextlib/winico/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  setup.rb   --   setup script before calling TkPackage.require()
 #
diff --git a/ext/tk/lib/tkextlib/winico/winico.rb b/ext/tk/lib/tkextlib/winico/winico.rb
index 9160c2960f..dda0357a16 100644
--- a/ext/tk/lib/tkextlib/winico/winico.rb
+++ b/ext/tk/lib/tkextlib/winico/winico.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #  tkextlib/winico/winico.rb
 #                               by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkfont.rb b/ext/tk/lib/tkfont.rb
index 38a96633de..6036006aac 100644
--- a/ext/tk/lib/tkfont.rb
+++ b/ext/tk/lib/tkfont.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tkfont.rb - load tk/font.rb
 #
diff --git a/ext/tk/lib/tkmacpkg.rb b/ext/tk/lib/tkmacpkg.rb
index 35560e78ce..4f76c2feb8 100644
--- a/ext/tk/lib/tkmacpkg.rb
+++ b/ext/tk/lib/tkmacpkg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tkmacpkg.rb - load tk/macpkg.rb
 #
diff --git a/ext/tk/lib/tkmenubar.rb b/ext/tk/lib/tkmenubar.rb
index 70214fda1a..43109e2b67 100644
--- a/ext/tk/lib/tkmenubar.rb
+++ b/ext/tk/lib/tkmenubar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tkmenubar.rb - load tk/menubar.rb
 #
diff --git a/ext/tk/lib/tkmngfocus.rb b/ext/tk/lib/tkmngfocus.rb
index fe70950e8e..43abd210c9 100644
--- a/ext/tk/lib/tkmngfocus.rb
+++ b/ext/tk/lib/tkmngfocus.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tkmngfocus.rb - load tk/mngfocus.rb
 #
diff --git a/ext/tk/lib/tkpalette.rb b/ext/tk/lib/tkpalette.rb
index 56b203bbb9..f4e7321c47 100644
--- a/ext/tk/lib/tkpalette.rb
+++ b/ext/tk/lib/tkpalette.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tkpalette.rb - load tk/palette.rb
 #
diff --git a/ext/tk/lib/tkscrollbox.rb b/ext/tk/lib/tkscrollbox.rb
index 6093b2e4e7..c316ce2ea6 100644
--- a/ext/tk/lib/tkscrollbox.rb
+++ b/ext/tk/lib/tkscrollbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tkscrollbox.rb - load tk/scrollbox.rb
 #
diff --git a/ext/tk/lib/tktext.rb b/ext/tk/lib/tktext.rb
index 97ad62a3ea..8ed41ac15a 100644
--- a/ext/tk/lib/tktext.rb
+++ b/ext/tk/lib/tktext.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tktext.rb - load tk/text.rb
 #
diff --git a/ext/tk/lib/tkvirtevent.rb b/ext/tk/lib/tkvirtevent.rb
index f4fae19a0a..4efa790505 100644
--- a/ext/tk/lib/tkvirtevent.rb
+++ b/ext/tk/lib/tkvirtevent.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tkvirtevent.rb - load tk/virtevent.rb
 #
diff --git a/ext/tk/lib/tkwinpkg.rb b/ext/tk/lib/tkwinpkg.rb
index 83371c546d..97c84f8ab1 100644
--- a/ext/tk/lib/tkwinpkg.rb
+++ b/ext/tk/lib/tkwinpkg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 #
 #   tkwinpkg.rb - load tk/winpkg.rb
 #
-- 
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