--- a/ThirdParty/Pygments/pygments/lexer.py Tue Jan 04 17:37:48 2011 +0100
+++ b/ThirdParty/Pygments/pygments/lexer.py Wed Jan 05 15:46:19 2011 +0100
@@ -1,658 +1,675 @@
-# -*- coding: utf-8 -*-
-"""
- pygments.lexer
- ~~~~~~~~~~~~~~
-
- Base lexer classes.
-
- :copyright: Copyright 2006-2010 by the Pygments team, see AUTHORS.
- :license: BSD, see LICENSE for details.
-"""
-import re
-
-from pygments.filter import apply_filters, Filter
-from pygments.filters import get_filter_by_name
-from pygments.token import Error, Text, Other, _TokenType
-from pygments.util import get_bool_opt, get_int_opt, get_list_opt, \
- make_analysator
-import collections
-
-
-__all__ = ['Lexer', 'RegexLexer', 'ExtendedRegexLexer', 'DelegatingLexer',
- 'LexerContext', 'include', 'bygroups', 'using', 'this']
-
-
-_default_analyse = staticmethod(lambda x: 0.0)
-
-
-class LexerMeta(type):
- """
- This metaclass automagically converts ``analyse_text`` methods into
- static methods which always return float values.
- """
-
- def __new__(cls, name, bases, d):
- if 'analyse_text' in d:
- d['analyse_text'] = make_analysator(d['analyse_text'])
- return type.__new__(cls, name, bases, d)
-
-
-class Lexer(object, metaclass=LexerMeta):
- """
- Lexer for a specific language.
-
- Basic options recognized:
- ``stripnl``
- Strip leading and trailing newlines from the input (default: True).
- ``stripall``
- Strip all leading and trailing whitespace from the input
- (default: False).
- ``ensurenl``
- Make sure that the input ends with a newline (default: True). This
- is required for some lexers that consume input linewise.
- *New in Pygments 1.3.*
- ``tabsize``
- If given and greater than 0, expand tabs in the input (default: 0).
- ``encoding``
- If given, must be an encoding name. This encoding will be used to
- convert the input string to Unicode, if it is not already a Unicode
- string (default: ``'latin1'``).
- Can also be ``'guess'`` to use a simple UTF-8 / Latin1 detection, or
- ``'chardet'`` to use the chardet library, if it is installed.
- """
-
- #: Name of the lexer
- name = None
-
- #: Shortcuts for the lexer
- aliases = []
-
- #: fn match rules
- filenames = []
-
- #: fn alias filenames
- alias_filenames = []
-
- #: mime types
- mimetypes = []
-
- def __init__(self, **options):
- self.options = options
- self.stripnl = get_bool_opt(options, 'stripnl', True)
- self.stripall = get_bool_opt(options, 'stripall', False)
- self.ensurenl = get_bool_opt(options, 'ensurenl', True)
- self.tabsize = get_int_opt(options, 'tabsize', 0)
- self.encoding = options.get('encoding', 'latin1')
- # self.encoding = options.get('inencoding', None) or self.encoding
- self.filters = []
- for filter_ in get_list_opt(options, 'filters', ()):
- self.add_filter(filter_)
-
- def __repr__(self):
- if self.options:
- return '<pygments.lexers.%s with %r>' % (self.__class__.__name__,
- self.options)
- else:
- return '<pygments.lexers.%s>' % self.__class__.__name__
-
- def add_filter(self, filter_, **options):
- """
- Add a new stream filter to this lexer.
- """
- if not isinstance(filter_, Filter):
- filter_ = get_filter_by_name(filter_, **options)
- self.filters.append(filter_)
-
- def analyse_text(text):
- """
- Has to return a float between ``0`` and ``1`` that indicates
- if a lexer wants to highlight this text. Used by ``guess_lexer``.
- If this method returns ``0`` it won't highlight it in any case, if
- it returns ``1`` highlighting with this lexer is guaranteed.
-
- The `LexerMeta` metaclass automatically wraps this function so
- that it works like a static method (no ``self`` or ``cls``
- parameter) and the return value is automatically converted to
- `float`. If the return value is an object that is boolean `False`
- it's the same as if the return values was ``0.0``.
- """
-
- def get_tokens(self, text, unfiltered=False):
- """
- Return an iterable of (tokentype, value) pairs generated from
- `text`. If `unfiltered` is set to `True`, the filtering mechanism
- is bypassed even if filters are defined.
-
- Also preprocess the text, i.e. expand tabs and strip it if
- wanted and applies registered filters.
- """
- if not isinstance(text, str):
- if self.encoding == 'guess':
- try:
- text = text.decode('utf-8')
- if text.startswith('\ufeff'):
- text = text[len('\ufeff'):]
- except UnicodeDecodeError:
- text = text.decode('latin1')
- elif self.encoding == 'chardet':
- try:
- import chardet
- except ImportError:
- raise ImportError('To enable chardet encoding guessing, '
- 'please install the chardet library '
- 'from http://chardet.feedparser.org/')
- enc = chardet.detect(text)
- text = text.decode(enc['encoding'])
- else:
- text = text.decode(self.encoding)
- # text now *is* a unicode string
- text = text.replace('\r\n', '\n')
- text = text.replace('\r', '\n')
- if self.stripall:
- text = text.strip()
- elif self.stripnl:
- text = text.strip('\n')
- if self.tabsize > 0:
- text = text.expandtabs(self.tabsize)
- if self.ensurenl and not text.endswith('\n'):
- text += '\n'
-
- def streamer():
- for i, t, v in self.get_tokens_unprocessed(text):
- yield t, v
- stream = streamer()
- if not unfiltered:
- stream = apply_filters(stream, self.filters, self)
- return stream
-
- def get_tokens_unprocessed(self, text):
- """
- Return an iterable of (tokentype, value) pairs.
- In subclasses, implement this method as a generator to
- maximize effectiveness.
- """
- raise NotImplementedError
-
-
-class DelegatingLexer(Lexer):
- """
- This lexer takes two lexer as arguments. A root lexer and
- a language lexer. First everything is scanned using the language
- lexer, afterwards all ``Other`` tokens are lexed using the root
- lexer.
-
- The lexers from the ``template`` lexer package use this base lexer.
- """
-
- def __init__(self, _root_lexer, _language_lexer, _needle=Other, **options):
- self.root_lexer = _root_lexer(**options)
- self.language_lexer = _language_lexer(**options)
- self.needle = _needle
- Lexer.__init__(self, **options)
-
- def get_tokens_unprocessed(self, text):
- buffered = ''
- insertions = []
- lng_buffer = []
- for i, t, v in self.language_lexer.get_tokens_unprocessed(text):
- if t is self.needle:
- if lng_buffer:
- insertions.append((len(buffered), lng_buffer))
- lng_buffer = []
- buffered += v
- else:
- lng_buffer.append((i, t, v))
- if lng_buffer:
- insertions.append((len(buffered), lng_buffer))
- return do_insertions(insertions,
- self.root_lexer.get_tokens_unprocessed(buffered))
-
-
-#-------------------------------------------------------------------------------
-# RegexLexer and ExtendedRegexLexer
-#
-
-
-class include(str):
- """
- Indicates that a state should include rules from another state.
- """
- pass
-
-
-class combined(tuple):
- """
- Indicates a state combined from multiple states.
- """
-
- def __new__(cls, *args):
- return tuple.__new__(cls, args)
-
- def __init__(self, *args):
- # tuple.__init__ doesn't do anything
- pass
-
-
-class _PseudoMatch(object):
- """
- A pseudo match object constructed from a string.
- """
-
- def __init__(self, start, text):
- self._text = text
- self._start = start
-
- def start(self, arg=None):
- return self._start
-
- def end(self, arg=None):
- return self._start + len(self._text)
-
- def group(self, arg=None):
- if arg:
- raise IndexError('No such group')
- return self._text
-
- def groups(self):
- return (self._text,)
-
- def groupdict(self):
- return {}
-
-
-def bygroups(*args):
- """
- Callback that yields multiple actions for each group in the match.
- """
- def callback(lexer, match, ctx=None):
- for i, action in enumerate(args):
- if action is None:
- continue
- elif type(action) is _TokenType:
- data = match.group(i + 1)
- if data:
- yield match.start(i + 1), action, data
- else:
- if ctx:
- ctx.pos = match.start(i + 1)
- for item in action(lexer, _PseudoMatch(match.start(i + 1),
- match.group(i + 1)), ctx):
- if item:
- yield item
- if ctx:
- ctx.pos = match.end()
- return callback
-
-
-class _This(object):
- """
- Special singleton used for indicating the caller class.
- Used by ``using``.
- """
-this = _This()
-
-
-def using(_other, **kwargs):
- """
- Callback that processes the match with a different lexer.
-
- The keyword arguments are forwarded to the lexer, except `state` which
- is handled separately.
-
- `state` specifies the state that the new lexer will start in, and can
- be an enumerable such as ('root', 'inline', 'string') or a simple
- string which is assumed to be on top of the root state.
-
- Note: For that to work, `_other` must not be an `ExtendedRegexLexer`.
- """
- gt_kwargs = {}
- if 'state' in kwargs:
- s = kwargs.pop('state')
- if isinstance(s, (list, tuple)):
- gt_kwargs['stack'] = s
- else:
- gt_kwargs['stack'] = ('root', s)
-
- if _other is this:
- def callback(lexer, match, ctx=None):
- # if keyword arguments are given the callback
- # function has to create a new lexer instance
- if kwargs:
- # XXX: cache that somehow
- kwargs.update(lexer.options)
- lx = lexer.__class__(**kwargs)
- else:
- lx = lexer
- s = match.start()
- for i, t, v in lx.get_tokens_unprocessed(match.group(), **gt_kwargs):
- yield i + s, t, v
- if ctx:
- ctx.pos = match.end()
- else:
- def callback(lexer, match, ctx=None):
- # XXX: cache that somehow
- kwargs.update(lexer.options)
- lx = _other(**kwargs)
-
- s = match.start()
- for i, t, v in lx.get_tokens_unprocessed(match.group(), **gt_kwargs):
- yield i + s, t, v
- if ctx:
- ctx.pos = match.end()
- return callback
-
-
-class RegexLexerMeta(LexerMeta):
- """
- Metaclass for RegexLexer, creates the self._tokens attribute from
- self.tokens on the first instantiation.
- """
-
- def _process_state(cls, unprocessed, processed, state):
- assert type(state) is str, "wrong state name %r" % state
- assert state[0] != '#', "invalid state name %r" % state
- if state in processed:
- return processed[state]
- tokens = processed[state] = []
- rflags = cls.flags
- for tdef in unprocessed[state]:
- if isinstance(tdef, include):
- # it's a state reference
- assert tdef != state, "circular state reference %r" % state
- tokens.extend(cls._process_state(unprocessed, processed, str(tdef)))
- continue
-
- assert type(tdef) is tuple, "wrong rule def %r" % tdef
-
- try:
- rex = re.compile(tdef[0], rflags).match
- except Exception as err:
- raise ValueError("uncompilable regex %r in state %r of %r: %s" %
- (tdef[0], state, cls, err))
-
- assert type(tdef[1]) is _TokenType or isinstance(tdef[1], collections.Callable), \
- 'token type must be simple type or callable, not %r' % (tdef[1],)
-
- if len(tdef) == 2:
- new_state = None
- else:
- tdef2 = tdef[2]
- if isinstance(tdef2, str):
- # an existing state
- if tdef2 == '#pop':
- new_state = -1
- elif tdef2 in unprocessed:
- new_state = (tdef2,)
- elif tdef2 == '#push':
- new_state = tdef2
- elif tdef2[:5] == '#pop:':
- new_state = -int(tdef2[5:])
- else:
- assert False, 'unknown new state %r' % tdef2
- elif isinstance(tdef2, combined):
- # combine a new state from existing ones
- new_state = '_tmp_%d' % cls._tmpname
- cls._tmpname += 1
- itokens = []
- for istate in tdef2:
- assert istate != state, 'circular state ref %r' % istate
- itokens.extend(cls._process_state(unprocessed,
- processed, istate))
- processed[new_state] = itokens
- new_state = (new_state,)
- elif isinstance(tdef2, tuple):
- # push more than one state
- for state in tdef2:
- assert (state in unprocessed or
- state in ('#pop', '#push')), \
- 'unknown new state ' + state
- new_state = tdef2
- else:
- assert False, 'unknown new state def %r' % tdef2
- tokens.append((rex, tdef[1], new_state))
- return tokens
-
- def process_tokendef(cls, name, tokendefs=None):
- processed = cls._all_tokens[name] = {}
- tokendefs = tokendefs or cls.tokens[name]
- for state in list(list(tokendefs.keys())):
- cls._process_state(tokendefs, processed, state)
- return processed
-
- def __call__(cls, *args, **kwds):
- if not hasattr(cls, '_tokens'):
- cls._all_tokens = {}
- cls._tmpname = 0
- if hasattr(cls, 'token_variants') and cls.token_variants:
- # don't process yet
- pass
- else:
- cls._tokens = cls.process_tokendef('', cls.tokens)
-
- return type.__call__(cls, *args, **kwds)
-
-
-class RegexLexer(Lexer, metaclass=RegexLexerMeta):
- """
- Base for simple stateful regular expression-based lexers.
- Simplifies the lexing process so that you need only
- provide a list of states and regular expressions.
- """
-
- #: Flags for compiling the regular expressions.
- #: Defaults to MULTILINE.
- flags = re.MULTILINE
-
- #: Dict of ``{'state': [(regex, tokentype, new_state), ...], ...}``
- #:
- #: The initial state is 'root'.
- #: ``new_state`` can be omitted to signify no state transition.
- #: If it is a string, the state is pushed on the stack and changed.
- #: If it is a tuple of strings, all states are pushed on the stack and
- #: the current state will be the topmost.
- #: It can also be ``combined('state1', 'state2', ...)``
- #: to signify a new, anonymous state combined from the rules of two
- #: or more existing ones.
- #: Furthermore, it can be '#pop' to signify going back one step in
- #: the state stack, or '#push' to push the current state on the stack
- #: again.
- #:
- #: The tuple can also be replaced with ``include('state')``, in which
- #: case the rules from the state named by the string are included in the
- #: current one.
- tokens = {}
-
- def get_tokens_unprocessed(self, text, stack=('root',)):
- """
- Split ``text`` into (tokentype, text) pairs.
-
- ``stack`` is the inital stack (default: ``['root']``)
- """
- pos = 0
- tokendefs = self._tokens
- statestack = list(stack)
- statetokens = tokendefs[statestack[-1]]
- while 1:
- for rexmatch, action, new_state in statetokens:
- m = rexmatch(text, pos)
- if m:
- if type(action) is _TokenType:
- yield pos, action, m.group()
- else:
- for item in action(self, m):
- yield item
- pos = m.end()
- if new_state is not None:
- # state transition
- if isinstance(new_state, tuple):
- for state in new_state:
- if state == '#pop':
- statestack.pop()
- elif state == '#push':
- statestack.append(statestack[-1])
- else:
- statestack.append(state)
- elif isinstance(new_state, int):
- # pop
- del statestack[new_state:]
- elif new_state == '#push':
- statestack.append(statestack[-1])
- else:
- assert False, "wrong state def: %r" % new_state
- statetokens = tokendefs[statestack[-1]]
- break
- else:
- try:
- if text[pos] == '\n':
- # at EOL, reset state to "root"
- pos += 1
- statestack = ['root']
- statetokens = tokendefs['root']
- yield pos, Text, '\n'
- continue
- yield pos, Error, text[pos]
- pos += 1
- except IndexError:
- break
-
-
-class LexerContext(object):
- """
- A helper object that holds lexer position data.
- """
-
- def __init__(self, text, pos, stack=None, end=None):
- self.text = text
- self.pos = pos
- self.end = end or len(text) # end=0 not supported ;-)
- self.stack = stack or ['root']
-
- def __repr__(self):
- return 'LexerContext(%r, %r, %r)' % (
- self.text, self.pos, self.stack)
-
-
-class ExtendedRegexLexer(RegexLexer):
- """
- A RegexLexer that uses a context object to store its state.
- """
-
- def get_tokens_unprocessed(self, text=None, context=None):
- """
- Split ``text`` into (tokentype, text) pairs.
- If ``context`` is given, use this lexer context instead.
- """
- tokendefs = self._tokens
- if not context:
- ctx = LexerContext(text, 0)
- statetokens = tokendefs['root']
- else:
- ctx = context
- statetokens = tokendefs[ctx.stack[-1]]
- text = ctx.text
- while 1:
- for rexmatch, action, new_state in statetokens:
- m = rexmatch(text, ctx.pos, ctx.end)
- if m:
- if type(action) is _TokenType:
- yield ctx.pos, action, m.group()
- ctx.pos = m.end()
- else:
- for item in action(self, m, ctx):
- yield item
- if not new_state:
- # altered the state stack?
- statetokens = tokendefs[ctx.stack[-1]]
- # CAUTION: callback must set ctx.pos!
- if new_state is not None:
- # state transition
- if isinstance(new_state, tuple):
- ctx.stack.extend(new_state)
- elif isinstance(new_state, int):
- # pop
- del ctx.stack[new_state:]
- elif new_state == '#push':
- ctx.stack.append(ctx.stack[-1])
- else:
- assert False, "wrong state def: %r" % new_state
- statetokens = tokendefs[ctx.stack[-1]]
- break
- else:
- try:
- if ctx.pos >= ctx.end:
- break
- if text[ctx.pos] == '\n':
- # at EOL, reset state to "root"
- ctx.pos += 1
- ctx.stack = ['root']
- statetokens = tokendefs['root']
- yield ctx.pos, Text, '\n'
- continue
- yield ctx.pos, Error, text[ctx.pos]
- ctx.pos += 1
- except IndexError:
- break
-
-
-def do_insertions(insertions, tokens):
- """
- Helper for lexers which must combine the results of several
- sublexers.
-
- ``insertions`` is a list of ``(index, itokens)`` pairs.
- Each ``itokens`` iterable should be inserted at position
- ``index`` into the token stream given by the ``tokens``
- argument.
-
- The result is a combined token stream.
-
- TODO: clean up the code here.
- """
- insertions = iter(insertions)
- try:
- index, itokens = next(insertions)
- except StopIteration:
- # no insertions
- for item in tokens:
- yield item
- return
-
- realpos = None
- insleft = True
-
- # iterate over the token stream where we want to insert
- # the tokens from the insertion list.
- for i, t, v in tokens:
- # first iteration. store the postition of first item
- if realpos is None:
- realpos = i
- oldi = 0
- while insleft and i + len(v) >= index:
- tmpval = v[oldi:index - i]
- yield realpos, t, tmpval
- realpos += len(tmpval)
- for it_index, it_token, it_value in itokens:
- yield realpos, it_token, it_value
- realpos += len(it_value)
- oldi = index - i
- try:
- index, itokens = next(insertions)
- except StopIteration:
- insleft = False
- break # not strictly necessary
- yield realpos, t, v[oldi:]
- realpos += len(v) - oldi
-
- # leftover tokens
- while insleft:
- # no normal tokens, set realpos to zero
- realpos = realpos or 0
- for p, t, v in itokens:
- yield realpos, t, v
- realpos += len(v)
- try:
- index, itokens = next(insertions)
- except StopIteration:
- insleft = False
- break # not strictly necessary
-
+# -*- coding: utf-8 -*-
+"""
+ pygments.lexer
+ ~~~~~~~~~~~~~~
+
+ Base lexer classes.
+
+ :copyright: Copyright 2006-2010 by the Pygments team, see AUTHORS.
+ :license: BSD, see LICENSE for details.
+"""
+import re
+
+from pygments.filter import apply_filters, Filter
+from pygments.filters import get_filter_by_name
+from pygments.token import Error, Text, Other, _TokenType
+from pygments.util import get_bool_opt, get_int_opt, get_list_opt, \
+ make_analysator
+
+
+__all__ = ['Lexer', 'RegexLexer', 'ExtendedRegexLexer', 'DelegatingLexer',
+ 'LexerContext', 'include', 'bygroups', 'using', 'this']
+
+
+_default_analyse = staticmethod(lambda x: 0.0)
+
+
+class LexerMeta(type):
+ """
+ This metaclass automagically converts ``analyse_text`` methods into
+ static methods which always return float values.
+ """
+
+ def __new__(cls, name, bases, d):
+ if 'analyse_text' in d:
+ d['analyse_text'] = make_analysator(d['analyse_text'])
+ return type.__new__(cls, name, bases, d)
+
+
+class Lexer(object, metaclass=LexerMeta):
+ """
+ Lexer for a specific language.
+
+ Basic options recognized:
+ ``stripnl``
+ Strip leading and trailing newlines from the input (default: True).
+ ``stripall``
+ Strip all leading and trailing whitespace from the input
+ (default: False).
+ ``ensurenl``
+ Make sure that the input ends with a newline (default: True). This
+ is required for some lexers that consume input linewise.
+ *New in Pygments 1.3.*
+ ``tabsize``
+ If given and greater than 0, expand tabs in the input (default: 0).
+ ``encoding``
+ If given, must be an encoding name. This encoding will be used to
+ convert the input string to Unicode, if it is not already a Unicode
+ string (default: ``'latin1'``).
+ Can also be ``'guess'`` to use a simple UTF-8 / Latin1 detection, or
+ ``'chardet'`` to use the chardet library, if it is installed.
+ """
+
+ #: Name of the lexer
+ name = None
+
+ #: Shortcuts for the lexer
+ aliases = []
+
+ #: fn match rules
+ filenames = []
+
+ #: fn alias filenames
+ alias_filenames = []
+
+ #: mime types
+ mimetypes = []
+
+ def __init__(self, **options):
+ self.options = options
+ self.stripnl = get_bool_opt(options, 'stripnl', True)
+ self.stripall = get_bool_opt(options, 'stripall', False)
+ self.ensurenl = get_bool_opt(options, 'ensurenl', True)
+ self.tabsize = get_int_opt(options, 'tabsize', 0)
+ self.encoding = options.get('encoding', 'latin1')
+ # self.encoding = options.get('inencoding', None) or self.encoding
+ self.filters = []
+ for filter_ in get_list_opt(options, 'filters', ()):
+ self.add_filter(filter_)
+
+ def __repr__(self):
+ if self.options:
+ return '<pygments.lexers.%s with %r>' % (self.__class__.__name__,
+ self.options)
+ else:
+ return '<pygments.lexers.%s>' % self.__class__.__name__
+
+ def add_filter(self, filter_, **options):
+ """
+ Add a new stream filter to this lexer.
+ """
+ if not isinstance(filter_, Filter):
+ filter_ = get_filter_by_name(filter_, **options)
+ self.filters.append(filter_)
+
+ def analyse_text(text):
+ """
+ Has to return a float between ``0`` and ``1`` that indicates
+ if a lexer wants to highlight this text. Used by ``guess_lexer``.
+ If this method returns ``0`` it won't highlight it in any case, if
+ it returns ``1`` highlighting with this lexer is guaranteed.
+
+ The `LexerMeta` metaclass automatically wraps this function so
+ that it works like a static method (no ``self`` or ``cls``
+ parameter) and the return value is automatically converted to
+ `float`. If the return value is an object that is boolean `False`
+ it's the same as if the return values was ``0.0``.
+ """
+
+ def get_tokens(self, text, unfiltered=False):
+ """
+ Return an iterable of (tokentype, value) pairs generated from
+ `text`. If `unfiltered` is set to `True`, the filtering mechanism
+ is bypassed even if filters are defined.
+
+ Also preprocess the text, i.e. expand tabs and strip it if
+ wanted and applies registered filters.
+ """
+ if not isinstance(text, str):
+ if self.encoding == 'guess':
+ try:
+ text = text.decode('utf-8')
+ if text.startswith('\ufeff'):
+ text = text[len('\ufeff'):]
+ except UnicodeDecodeError:
+ text = text.decode('latin1')
+ elif self.encoding == 'chardet':
+ try:
+ import chardet
+ except ImportError:
+ raise ImportError('To enable chardet encoding guessing, '
+ 'please install the chardet library '
+ 'from http://chardet.feedparser.org/')
+ enc = chardet.detect(text)
+ text = text.decode(enc['encoding'])
+ else:
+ text = text.decode(self.encoding)
+ # text now *is* a unicode string
+ text = text.replace('\r\n', '\n')
+ text = text.replace('\r', '\n')
+ if self.stripall:
+ text = text.strip()
+ elif self.stripnl:
+ text = text.strip('\n')
+ if self.tabsize > 0:
+ text = text.expandtabs(self.tabsize)
+ if self.ensurenl and not text.endswith('\n'):
+ text += '\n'
+
+ def streamer():
+ for i, t, v in self.get_tokens_unprocessed(text):
+ yield t, v
+ stream = streamer()
+ if not unfiltered:
+ stream = apply_filters(stream, self.filters, self)
+ return stream
+
+ def get_tokens_unprocessed(self, text):
+ """
+ Return an iterable of (tokentype, value) pairs.
+ In subclasses, implement this method as a generator to
+ maximize effectiveness.
+ """
+ raise NotImplementedError
+
+
+class DelegatingLexer(Lexer):
+ """
+ This lexer takes two lexer as arguments. A root lexer and
+ a language lexer. First everything is scanned using the language
+ lexer, afterwards all ``Other`` tokens are lexed using the root
+ lexer.
+
+ The lexers from the ``template`` lexer package use this base lexer.
+ """
+
+ def __init__(self, _root_lexer, _language_lexer, _needle=Other, **options):
+ self.root_lexer = _root_lexer(**options)
+ self.language_lexer = _language_lexer(**options)
+ self.needle = _needle
+ Lexer.__init__(self, **options)
+
+ def get_tokens_unprocessed(self, text):
+ buffered = ''
+ insertions = []
+ lng_buffer = []
+ for i, t, v in self.language_lexer.get_tokens_unprocessed(text):
+ if t is self.needle:
+ if lng_buffer:
+ insertions.append((len(buffered), lng_buffer))
+ lng_buffer = []
+ buffered += v
+ else:
+ lng_buffer.append((i, t, v))
+ if lng_buffer:
+ insertions.append((len(buffered), lng_buffer))
+ return do_insertions(insertions,
+ self.root_lexer.get_tokens_unprocessed(buffered))
+
+
+#-------------------------------------------------------------------------------
+# RegexLexer and ExtendedRegexLexer
+#
+
+
+class include(str):
+ """
+ Indicates that a state should include rules from another state.
+ """
+ pass
+
+
+class combined(tuple):
+ """
+ Indicates a state combined from multiple states.
+ """
+
+ def __new__(cls, *args):
+ return tuple.__new__(cls, args)
+
+ def __init__(self, *args):
+ # tuple.__init__ doesn't do anything
+ pass
+
+
+class _PseudoMatch(object):
+ """
+ A pseudo match object constructed from a string.
+ """
+
+ def __init__(self, start, text):
+ self._text = text
+ self._start = start
+
+ def start(self, arg=None):
+ return self._start
+
+ def end(self, arg=None):
+ return self._start + len(self._text)
+
+ def group(self, arg=None):
+ if arg:
+ raise IndexError('No such group')
+ return self._text
+
+ def groups(self):
+ return (self._text,)
+
+ def groupdict(self):
+ return {}
+
+
+def bygroups(*args):
+ """
+ Callback that yields multiple actions for each group in the match.
+ """
+ def callback(lexer, match, ctx=None):
+ for i, action in enumerate(args):
+ if action is None:
+ continue
+ elif type(action) is _TokenType:
+ data = match.group(i + 1)
+ if data:
+ yield match.start(i + 1), action, data
+ else:
+ if ctx:
+ ctx.pos = match.start(i + 1)
+ for item in action(lexer, _PseudoMatch(match.start(i + 1),
+ match.group(i + 1)), ctx):
+ if item:
+ yield item
+ if ctx:
+ ctx.pos = match.end()
+ return callback
+
+
+class _This(object):
+ """
+ Special singleton used for indicating the caller class.
+ Used by ``using``.
+ """
+this = _This()
+
+
+def using(_other, **kwargs):
+ """
+ Callback that processes the match with a different lexer.
+
+ The keyword arguments are forwarded to the lexer, except `state` which
+ is handled separately.
+
+ `state` specifies the state that the new lexer will start in, and can
+ be an enumerable such as ('root', 'inline', 'string') or a simple
+ string which is assumed to be on top of the root state.
+
+ Note: For that to work, `_other` must not be an `ExtendedRegexLexer`.
+ """
+ gt_kwargs = {}
+ if 'state' in kwargs:
+ s = kwargs.pop('state')
+ if isinstance(s, (list, tuple)):
+ gt_kwargs['stack'] = s
+ else:
+ gt_kwargs['stack'] = ('root', s)
+
+ if _other is this:
+ def callback(lexer, match, ctx=None):
+ # if keyword arguments are given the callback
+ # function has to create a new lexer instance
+ if kwargs:
+ # XXX: cache that somehow
+ kwargs.update(lexer.options)
+ lx = lexer.__class__(**kwargs)
+ else:
+ lx = lexer
+ s = match.start()
+ for i, t, v in lx.get_tokens_unprocessed(match.group(), **gt_kwargs):
+ yield i + s, t, v
+ if ctx:
+ ctx.pos = match.end()
+ else:
+ def callback(lexer, match, ctx=None):
+ # XXX: cache that somehow
+ kwargs.update(lexer.options)
+ lx = _other(**kwargs)
+
+ s = match.start()
+ for i, t, v in lx.get_tokens_unprocessed(match.group(), **gt_kwargs):
+ yield i + s, t, v
+ if ctx:
+ ctx.pos = match.end()
+ return callback
+
+
+class RegexLexerMeta(LexerMeta):
+ """
+ Metaclass for RegexLexer, creates the self._tokens attribute from
+ self.tokens on the first instantiation.
+ """
+
+ def _process_regex(cls, regex, rflags):
+ """Preprocess the regular expression component of a token definition."""
+ return re.compile(regex, rflags).match
+
+ def _process_token(cls, token):
+ """Preprocess the token component of a token definition."""
+ assert type(token) is _TokenType or hasattr(token, '__call__'), \
+ 'token type must be simple type or callable, not %r' % (token,)
+ return token
+
+ def _process_new_state(cls, new_state, unprocessed, processed):
+ """Preprocess the state transition action of a token definition."""
+ if isinstance(new_state, str):
+ # an existing state
+ if new_state == '#pop':
+ return -1
+ elif new_state in unprocessed:
+ return (new_state,)
+ elif new_state == '#push':
+ return new_state
+ elif new_state[:5] == '#pop:':
+ return -int(new_state[5:])
+ else:
+ assert False, 'unknown new state %r' % new_state
+ elif isinstance(new_state, combined):
+ # combine a new state from existing ones
+ tmp_state = '_tmp_%d' % cls._tmpname
+ cls._tmpname += 1
+ itokens = []
+ for istate in new_state:
+ assert istate != new_state, 'circular state ref %r' % istate
+ itokens.extend(cls._process_state(unprocessed,
+ processed, istate))
+ processed[tmp_state] = itokens
+ return (tmp_state,)
+ elif isinstance(new_state, tuple):
+ # push more than one state
+ for istate in new_state:
+ assert (istate in unprocessed or
+ istate in ('#pop', '#push')), \
+ 'unknown new state ' + istate
+ return new_state
+ else:
+ assert False, 'unknown new state def %r' % new_state
+
+ def _process_state(cls, unprocessed, processed, state):
+ """Preprocess a single state definition."""
+ assert type(state) is str, "wrong state name %r" % state
+ assert state[0] != '#', "invalid state name %r" % state
+ if state in processed:
+ return processed[state]
+ tokens = processed[state] = []
+ rflags = cls.flags
+ for tdef in unprocessed[state]:
+ if isinstance(tdef, include):
+ # it's a state reference
+ assert tdef != state, "circular state reference %r" % state
+ tokens.extend(cls._process_state(unprocessed, processed,
+ str(tdef)))
+ continue
+
+ assert type(tdef) is tuple, "wrong rule def %r" % tdef
+
+ try:
+ rex = cls._process_regex(tdef[0], rflags)
+ except Exception as err:
+ raise ValueError("uncompilable regex %r in state %r of %r: %s" %
+ (tdef[0], state, cls, err))
+
+ token = cls._process_token(tdef[1])
+
+ if len(tdef) == 2:
+ new_state = None
+ else:
+ new_state = cls._process_new_state(tdef[2],
+ unprocessed, processed)
+
+ tokens.append((rex, token, new_state))
+ return tokens
+
+ def process_tokendef(cls, name, tokendefs=None):
+ """Preprocess a dictionary of token definitions."""
+ processed = cls._all_tokens[name] = {}
+ tokendefs = tokendefs or cls.tokens[name]
+ for state in list(tokendefs.keys()):
+ cls._process_state(tokendefs, processed, state)
+ return processed
+
+ def __call__(cls, *args, **kwds):
+ """Instantiate cls after preprocessing its token definitions."""
+ if not hasattr(cls, '_tokens'):
+ cls._all_tokens = {}
+ cls._tmpname = 0
+ if hasattr(cls, 'token_variants') and cls.token_variants:
+ # don't process yet
+ pass
+ else:
+ cls._tokens = cls.process_tokendef('', cls.tokens)
+
+ return type.__call__(cls, *args, **kwds)
+
+
+class RegexLexer(Lexer, metaclass=RegexLexerMeta):
+ """
+ Base for simple stateful regular expression-based lexers.
+ Simplifies the lexing process so that you need only
+ provide a list of states and regular expressions.
+ """
+
+ #: Flags for compiling the regular expressions.
+ #: Defaults to MULTILINE.
+ flags = re.MULTILINE
+
+ #: Dict of ``{'state': [(regex, tokentype, new_state), ...], ...}``
+ #:
+ #: The initial state is 'root'.
+ #: ``new_state`` can be omitted to signify no state transition.
+ #: If it is a string, the state is pushed on the stack and changed.
+ #: If it is a tuple of strings, all states are pushed on the stack and
+ #: the current state will be the topmost.
+ #: It can also be ``combined('state1', 'state2', ...)``
+ #: to signify a new, anonymous state combined from the rules of two
+ #: or more existing ones.
+ #: Furthermore, it can be '#pop' to signify going back one step in
+ #: the state stack, or '#push' to push the current state on the stack
+ #: again.
+ #:
+ #: The tuple can also be replaced with ``include('state')``, in which
+ #: case the rules from the state named by the string are included in the
+ #: current one.
+ tokens = {}
+
+ def get_tokens_unprocessed(self, text, stack=('root',)):
+ """
+ Split ``text`` into (tokentype, text) pairs.
+
+ ``stack`` is the inital stack (default: ``['root']``)
+ """
+ pos = 0
+ tokendefs = self._tokens
+ statestack = list(stack)
+ statetokens = tokendefs[statestack[-1]]
+ while 1:
+ for rexmatch, action, new_state in statetokens:
+ m = rexmatch(text, pos)
+ if m:
+ if type(action) is _TokenType:
+ yield pos, action, m.group()
+ else:
+ for item in action(self, m):
+ yield item
+ pos = m.end()
+ if new_state is not None:
+ # state transition
+ if isinstance(new_state, tuple):
+ for state in new_state:
+ if state == '#pop':
+ statestack.pop()
+ elif state == '#push':
+ statestack.append(statestack[-1])
+ else:
+ statestack.append(state)
+ elif isinstance(new_state, int):
+ # pop
+ del statestack[new_state:]
+ elif new_state == '#push':
+ statestack.append(statestack[-1])
+ else:
+ assert False, "wrong state def: %r" % new_state
+ statetokens = tokendefs[statestack[-1]]
+ break
+ else:
+ try:
+ if text[pos] == '\n':
+ # at EOL, reset state to "root"
+ pos += 1
+ statestack = ['root']
+ statetokens = tokendefs['root']
+ yield pos, Text, '\n'
+ continue
+ yield pos, Error, text[pos]
+ pos += 1
+ except IndexError:
+ break
+
+
+class LexerContext(object):
+ """
+ A helper object that holds lexer position data.
+ """
+
+ def __init__(self, text, pos, stack=None, end=None):
+ self.text = text
+ self.pos = pos
+ self.end = end or len(text) # end=0 not supported ;-)
+ self.stack = stack or ['root']
+
+ def __repr__(self):
+ return 'LexerContext(%r, %r, %r)' % (
+ self.text, self.pos, self.stack)
+
+
+class ExtendedRegexLexer(RegexLexer):
+ """
+ A RegexLexer that uses a context object to store its state.
+ """
+
+ def get_tokens_unprocessed(self, text=None, context=None):
+ """
+ Split ``text`` into (tokentype, text) pairs.
+ If ``context`` is given, use this lexer context instead.
+ """
+ tokendefs = self._tokens
+ if not context:
+ ctx = LexerContext(text, 0)
+ statetokens = tokendefs['root']
+ else:
+ ctx = context
+ statetokens = tokendefs[ctx.stack[-1]]
+ text = ctx.text
+ while 1:
+ for rexmatch, action, new_state in statetokens:
+ m = rexmatch(text, ctx.pos, ctx.end)
+ if m:
+ if type(action) is _TokenType:
+ yield ctx.pos, action, m.group()
+ ctx.pos = m.end()
+ else:
+ for item in action(self, m, ctx):
+ yield item
+ if not new_state:
+ # altered the state stack?
+ statetokens = tokendefs[ctx.stack[-1]]
+ # CAUTION: callback must set ctx.pos!
+ if new_state is not None:
+ # state transition
+ if isinstance(new_state, tuple):
+ ctx.stack.extend(new_state)
+ elif isinstance(new_state, int):
+ # pop
+ del ctx.stack[new_state:]
+ elif new_state == '#push':
+ ctx.stack.append(ctx.stack[-1])
+ else:
+ assert False, "wrong state def: %r" % new_state
+ statetokens = tokendefs[ctx.stack[-1]]
+ break
+ else:
+ try:
+ if ctx.pos >= ctx.end:
+ break
+ if text[ctx.pos] == '\n':
+ # at EOL, reset state to "root"
+ ctx.pos += 1
+ ctx.stack = ['root']
+ statetokens = tokendefs['root']
+ yield ctx.pos, Text, '\n'
+ continue
+ yield ctx.pos, Error, text[ctx.pos]
+ ctx.pos += 1
+ except IndexError:
+ break
+
+
+def do_insertions(insertions, tokens):
+ """
+ Helper for lexers which must combine the results of several
+ sublexers.
+
+ ``insertions`` is a list of ``(index, itokens)`` pairs.
+ Each ``itokens`` iterable should be inserted at position
+ ``index`` into the token stream given by the ``tokens``
+ argument.
+
+ The result is a combined token stream.
+
+ TODO: clean up the code here.
+ """
+ insertions = iter(insertions)
+ try:
+ index, itokens = next(insertions)
+ except StopIteration:
+ # no insertions
+ for item in tokens:
+ yield item
+ return
+
+ realpos = None
+ insleft = True
+
+ # iterate over the token stream where we want to insert
+ # the tokens from the insertion list.
+ for i, t, v in tokens:
+ # first iteration. store the postition of first item
+ if realpos is None:
+ realpos = i
+ oldi = 0
+ while insleft and i + len(v) >= index:
+ tmpval = v[oldi:index - i]
+ yield realpos, t, tmpval
+ realpos += len(tmpval)
+ for it_index, it_token, it_value in itokens:
+ yield realpos, it_token, it_value
+ realpos += len(it_value)
+ oldi = index - i
+ try:
+ index, itokens = next(insertions)
+ except StopIteration:
+ insleft = False
+ break # not strictly necessary
+ yield realpos, t, v[oldi:]
+ realpos += len(v) - oldi
+
+ # leftover tokens
+ while insleft:
+ # no normal tokens, set realpos to zero
+ realpos = realpos or 0
+ for p, t, v in itokens:
+ yield realpos, t, v
+ realpos += len(v)
+ try:
+ index, itokens = next(insertions)
+ except StopIteration:
+ insleft = False
+ break # not strictly necessary
+
