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# Copyright (c) 2006-2009 Nathan Binkert <nate@binkert.org>
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met: redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer;
# redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution;
# neither the name of the copyright holders nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
from ply import lex, yacc
class TokenError(lex.LexError):
def __init__(self, msg, t):
super(TokenError, self).__init__(msg)
self.token = t
class ParseError(yacc.YaccError):
def __init__(self, message, token=None):
super(ParseError, self).__init__(message)
self.token = token
class Tokenizer(object):
def __init__(self, lexer, data):
if isinstance(data, basestring):
indata = [ data ]
elif isinstance(data, file):
indata = data.xreadlines()
else:
indata = data
def _input():
for i,line in enumerate(indata):
lexer.lineno = i + 1
lexer.input(line)
while True:
tok = lexer.token()
if not tok:
break
yield tok
self.input = _input()
def next(self):
return self.input.next()
def __iter__(self):
return self
def token(self):
try:
return self.next()
except StopIteration:
return None
class Grammar(object):
def __init__(self, output=None, debug=False):
self.yacc_args = {}
self.yacc_args['debug'] = debug
if output:
import os
dir,tab = os.path.split(output)
if not tab.endswith('.py'):
raise AttributeError, 'The output file must end with .py'
self.yacc_args['outputdir'] = dir
self.yacc_args['tabmodule'] = tab[:-3]
def t_error(self, t):
raise lex.LexError("Illegal character %s @ %d:%d" % \
(`t.value[0]`, t.lineno, t.lexpos), `t.value[0]`)
def p_error(self, t):
if t:
msg = "Syntax error at %d:%d\n>>%s<<" % \
(t.lineno, t.lexpos + 1, t.value)
else:
msg = "Syntax error at end of input"
raise ParseError(msg, t)
def __getattr__(self, attr):
if attr == 'parser':
import ply.yacc
parser = ply.yacc.yacc(module=self, **self.yacc_args)
self.parser = parser
return parser
if attr == 'lexer':
import ply.lex
lexer = ply.lex.lex(module=self)
self.lexer = lexer
return lexer
raise AttributeError, "'%s' object has no attribute '%s'" % \
(self.__class__.__name__, attr)
def parse(self, stmt, **kwargs):
self.lexer.lineno = 1
result = self.parser.parse(lexer=Tokenizer(self.lexer, stmt), **kwargs)
self.parser.restart()
return result
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