1 files changed, 57 insertions, 0 deletions
diff --git a/ext/ripper/tools/preproc.rb b/ext/ripper/tools/preproc.rb
new file mode 100755
index 0000000000..a2dba36e02
--- /dev/null
+++ b/ext/ripper/tools/preproc.rb
@@ -0,0 +1,57 @@
+def main
+  prelude
+  grammar
+  usercode
+end
+
+def prelude
+  while line = ARGF.gets
+    case line
+    when %r</\*%%%\*/>
+      puts '/*'
+    when %r</\*%>
+      puts '*/'
+    when %r<%\*/>
+      puts
+    when /\A%%/
+      puts '%%'
+      return
+    when /\A%token/
+      puts line.sub(/<\w+>/, '<val>')
+    when /\A%type/
+      puts line.sub(/<\w+>/, '<val>')
+    else
+      print line
+    end
+  end
+end
+
+def grammar
+  while line = ARGF.gets
+    case line
+    when %r</\*%%%\*/>
+      puts '#if 0'
+    when %r</\*%c%\*/>
+      puts '/*'
+    when %r</\*%c>
+      puts '*/'
+    when %r</\*%>
+      puts '#endif'
+    when %r<%\*/>
+      puts
+    when /\A%%/
+      puts '%%'
+      return
+    else
+      print line
+    end
+  end
+end
+
+def usercode
+  while line = ARGF.gets
+    print line
+  end
+end
+
+main