#!/usr/bin/python2
#
# Yapps 2 - yet another python parser system
# Copyright 1999-2003 by Amit J. Patel <amitp@cs.stanford.edu>
#
# This version of Yapps 2 can be distributed under the
# terms of the MIT open source license, either found in the LICENSE file
# included with the Yapps distribution
# <http://theory.stanford.edu/~amitp/yapps/> or at
# <http://www.opensource.org/licenses/mit-license.php>
#
import sys, re
import yappsrt, parsetree
def generate(inputfilename, outputfilename='', dump=0, **flags):
"""Generate a grammar, given an input filename (X.g)
and an output filename (defaulting to X.py)."""
if not outputfilename:
if inputfilename.endswith('.g'):
outputfilename = inputfilename[:-2] + '.py'
else:
raise Exception('Must specify output filename if input filename is not *.g')
DIVIDER = '\n%%\n' # This pattern separates the pre/post parsers
preparser, postparser = None, None # Code before and after the parser desc
# Read the entire file
s = open(inputfilename,'r').read()
# See if there's a separation between the pre-parser and parser
f = s.find(DIVIDER)
if f >= 0: preparser, s = s[:f]+'\n\n', s[f+len(DIVIDER):]
# See if there's a separation between the parser and post-parser
f = s.find(DIVIDER)
if f >= 0: s, postparser = s[:f], '\n\n'+s[f+len(DIVIDER):]
# Create the parser and scanner and parse the text
scanner = grammar.ParserDescriptionScanner(s)
if preparser: scanner.first_line_number = 1 + preparser.count('\n')
parser = grammar.ParserDescription(scanner)
t = yappsrt.wrap_error_reporter(parser, 'Parser')
if t is None: return # Failure
if preparser is not None: t.preparser = preparser
if postparser is not None: t.postparser = postparser
# Check the options
for f in t.options.keys():
for opt,_,_ in yapps_options:
if f == opt: break
else:
print >>sys.stderr, 'Warning: unrecognized option', f
# Add command line options to the set
for f in flags.keys(): t.options[f] = flags[f]
# Generate the output
if dump:
t.dump_information()
else:
t.output = open(outputfilename, 'w')
t.generate_output()
if __name__ == '__main__':
import doctest
doctest.testmod(sys.modules['__main__'])
doctest.testmod(parsetree)
# Someday I will use optparse, but Python 2.3 is too new at the moment.
yapps_options = [
('context-insensitive-scanner',
'context-insensitive-scanner',
'Scan all tokens (see docs)'),
]
import getopt
optlist, args = getopt.getopt(sys.argv[1:], 'f:', ['help', 'dump', 'use-devel-grammar'])
if not args or len(args) > 2:
print >>sys.stderr, 'Usage:'
print >>sys.stderr, ' python', sys.argv[0], '[flags] input.g [output.py]'
print >>sys.stderr, 'Flags:'
print >>sys.stderr, (' --dump' + ' '*40)[:35] + 'Dump out grammar information'
print >>sys.stderr, (' --use-devel-grammar' + ' '*40)[:35] + 'Use the devel grammar parser from yapps_grammar.py instead of the stable grammar from grammar.py'
for flag, _, doc in yapps_options:
print >>sys.stderr, (' -f' + flag + ' '*40)[:35] + doc
else:
# Read in the options and create a list of flags
flags = {}
use_devel_grammar = 0
for opt in optlist:
for flag, name, _ in yapps_options:
if opt == ('-f', flag):
flags[name] = 1
break
else:
if opt == ('--dump', ''):
flags['dump'] = 1
elif opt == ('--use-devel-grammar', ''):
use_devel_grammar = 1
else:
print >>sys.stderr, 'Warning: unrecognized option', opt[0], opt[1]
if use_devel_grammar:
import yapps_grammar as grammar
else:
import grammar
generate(*tuple(args), **flags)
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