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+#!/usr/local/bin/python
+# yply.py
+#
+# Author: David Beazley (dave@dabeaz.com)
+# Date : October 2, 2006
+#
+# Converts a UNIX-yacc specification file into a PLY-compatible
+# specification. To use, simply do this:
+#
+# % python yply.py [-nocode] inputfile.y >myparser.py
+#
+# The output of this program is Python code. In the output,
+# any C code in the original file is included, but is commented.
+# If you use the -nocode option, then all of the C code in the
+# original file is discarded.
+#
+# Disclaimer: This just an example I threw together in an afternoon.
+# It might have some bugs. However, it worked when I tried it on
+# a yacc-specified C++ parser containing 442 rules and 855 parsing
+# states.
+#
+
+import sys
+sys.path.insert(0,"../..")
+
+import ylex
+import yparse
+
+from ply import *
+
+if len(sys.argv) == 1:
+ print "usage : yply.py [-nocode] inputfile"
+ raise SystemExit
+
+if len(sys.argv) == 3:
+ if sys.argv[1] == '-nocode':
+ yparse.emit_code = 0
+ else:
+ print "Unknown option '%s'" % sys.argv[1]
+ raise SystemExit
+ filename = sys.argv[2]
+else:
+ filename = sys.argv[1]
+
+yacc.parse(open(filename).read())
+
+print """
+if __name__ == '__main__':
+ from ply import *
+ yacc.yacc()
+"""
+
+