1 files changed, 44 insertions, 0 deletions
diff --git a/ext/ripper/tools/generate-ripper_rb.rb b/ext/ripper/tools/generate-ripper_rb.rb
new file mode 100755
index 0000000000..c6b2aea13f
--- /dev/null
+++ b/ext/ripper/tools/generate-ripper_rb.rb
@@ -0,0 +1,44 @@
+#
+# generate-ripper_rb.rb
+# Creates ripper.rb, filling in default event handlers, given a basic 
+# template, the list of parser events (ids1), and a list of lexer 
+# events (ids2).
+#
+
+def main
+  template, ids1, ids2 = *ARGV
+  File.foreach(template) do |line|
+    case line
+    when /\A\#include handlers1/
+      File.foreach(ids1) do |line|
+        id, arity = line.split
+        arity = arity.to_i
+        puts
+        puts "  def on__#{id}(#{argdecl(arity)})"
+        puts "    #{arity == 0 ? 'nil' : 'a'}"
+        puts "  end"
+      end
+    when /\A\#include handlers2/
+      File.foreach(ids2) do |line|
+        id, arity = line.split
+        arity = arity.to_i
+        puts
+        puts "  def on__#{id}(token)"
+        puts "    token"
+        puts "  end"
+      end
+    when /\A\#include (.*)/
+      raise "unknown operation: #include #{$1}"
+    else
+      print line
+    end
+  end
+end
+
+# Generate generic arg list depending on arity (n)
+# n:: [Integer] arity of method
+def argdecl( n )
+  %w(a b c d e f g h i j k l m)[0, n].join(', ')
+end
+
+main