def __call__(self, tokenStream):
tokens = PrettyPrintingList()
for token in tokenStream:
if token.__class__ not in self._ignore:
tokens.append(token)
return (tokens, [])
def __call__(self, source):
# This approach is more memory intensive but so much simpler to get right.
characterStream = PrettyPrintingList()
while True:
# Be sure to get the position before reading the character.
position = source.tell()
char = source.read(1)
if not char:
break
else:
characterStream.append((char, position))
characterStream.append((EOFSymbol, source.tell()))
return (characterStream, [])
def __call__(self, charStream):
tokenStream = PrettyPrintingList()
issues = []
# This offset can be done away with and instead iterate over the stream.
offset = 0
while offset < len(charStream):
(numCharsMatched, tokenType) = self._longestMatch(charStream[offset:])
if numCharsMatched:
if tokenType != None:
# XXX should this be an ASSERT tokenType?
startIndex = charStream[offset][1]
try:
endIndex = charStream[offset + numCharsMatched][1]
matched = charStream[offset : offset + numCharsMatched]
except IndexError:
# It the file doesn't end with a newline.
endIndex = charStream[offset + numCharsMatched -1][1]
matched = charStream[offset : offset + numCharsMatched -1]
# XXX this is kind of ugly. Only certain token types need to
# hold on the the original character information for their
# values. In some cases this even involved re-scanning (eg:
# numeric literals).
lexeme = "".join([item[0] for item in matched])
nextTok = tokenType(startIndex, endIndex, lexeme)
tokenStream.append(nextTok)
offset += numCharsMatched
else:
# XXX Lots more smarts here in error recovery.
tokenStream = None
issues.append(UnexpectedSymbolError(charStream[offset][1],\
charStream[offset][1]))
break
# XXX jsut hack in the insertion of BOF and EOF for now
if tokenStream != None:
tokenStream.insert(0, token.BOF())
tokenStream.append(token.EOF())
return (tokenStream, issues)
