== \Regexps Based on Unicode Properties

The properties shown here are those currently supported in Ruby.
Older versions may not support all of these.
<%
# Generate a documentation file for the unicode properties.
#
# Usage:
#
# Get PropertyAliases.txt, PropertyValueAliases.txt from unicode.org
# (http://unicode.org/Public/UNIDATA/) and run
# ```
# ruby tool/generic_erb.rb template/unicode_properties.rdoc.tmpl data_dir name2ctype.h
# ```

data_dir = ARGV.shift&.tap { |d| Dir.exist?(d) } ||
  abort("Usage: #{$0} data_directory [name2ctype.h]")

# Map group names, given as last argument to #make_const in enc-unicode.rb,
# to sections in the doc. The order in this hash controls the order in the doc.
map = {
  /\[\[:/            => 'POSIX brackets',
  '-'                => 'Special',
  /.+ Category/      => 'Major and General Categories',
  'Binary Property'  => 'Prop List',
  /Derived Property/ => 'Derived Core Properties',
  'Script'           => 'Scripts',
  'Block'            => 'Blocks',
  'Emoji'            => 'Emoji',
  /Grapheme/         => 'Graphemes',
  /Derived Age/      => 'Derived Ages',
}

# aliases in the form { short => long }, e.g. { 'Hex' => 'Hex_Digit', 'L' => 'Letter' }
aliases = (
  File.binread(File.join(data_dir, 'PropertyAliases.txt')).scan(/^(\w+)\s*; (\w+)/) +
  File.binread(File.join(data_dir, 'PropertyValueAliases.txt')).scan(/^(?:gc|sc)\s*; (\w+)\s*; (\w+)/)
).to_h

props_by_section = {}
ARGF.each_line do |line|
  next unless /'(?<prop>[^']+)': (?<name>.+) \*/ =~ line
  next if prop == 'NEWLINE' # ignore custom internal prop

  section = map.find { |k, v| k === name }&.last || warn("no doc section for #{name}")

  # normalize prop names - the header file uses a mix of short and long names
  long_prop_name = aliases[prop] || prop
  (props_by_section[section] ||= []) << long_prop_name
end

map.each_value do |section| -%>

=== <%=section%>

%   props_by_section[section].sort.each do |prop|
- <%= [prop, aliases.key(prop)].compact.uniq.map { |v| "<tt>\\p{#{v}}</tt>" }.join(', ') %>
%   end
% end