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author | S. Solomon Darnell | 2025-03-28 21:52:21 -0500 |
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committer | S. Solomon Darnell | 2025-03-28 21:52:21 -0500 |
commit | 4a52a71956a8d46fcb7294ac71734504bb09bcc2 (patch) | |
tree | ee3dc5af3b6313e921cd920906356f5d4febc4ed /.venv/lib/python3.12/site-packages/lark/parser_frontends.py | |
parent | cc961e04ba734dd72309fb548a2f97d67d578813 (diff) | |
download | gn-ai-master.tar.gz |
Diffstat (limited to '.venv/lib/python3.12/site-packages/lark/parser_frontends.py')
-rw-r--r-- | .venv/lib/python3.12/site-packages/lark/parser_frontends.py | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/lark/parser_frontends.py b/.venv/lib/python3.12/site-packages/lark/parser_frontends.py new file mode 100644 index 00000000..0e53dd58 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/lark/parser_frontends.py @@ -0,0 +1,239 @@ +from .exceptions import ConfigurationError, GrammarError, assert_config +from .utils import get_regexp_width, Serialize +from .parsers.grammar_analysis import GrammarAnalyzer +from .lexer import LexerThread, TraditionalLexer, ContextualLexer, Lexer, Token, TerminalDef +from .parsers import earley, xearley, cyk +from .parsers.lalr_parser import LALR_Parser +from .tree import Tree +from .common import LexerConf, ParserConf +try: + import regex +except ImportError: + regex = None +import re + +###{standalone + +def _wrap_lexer(lexer_class): + future_interface = getattr(lexer_class, '__future_interface__', False) + if future_interface: + return lexer_class + else: + class CustomLexerWrapper(Lexer): + def __init__(self, lexer_conf): + self.lexer = lexer_class(lexer_conf) + def lex(self, lexer_state, parser_state): + return self.lexer.lex(lexer_state.text) + return CustomLexerWrapper + + +class MakeParsingFrontend: + def __init__(self, parser_type, lexer_type): + self.parser_type = parser_type + self.lexer_type = lexer_type + + def __call__(self, lexer_conf, parser_conf, options): + assert isinstance(lexer_conf, LexerConf) + assert isinstance(parser_conf, ParserConf) + parser_conf.parser_type = self.parser_type + lexer_conf.lexer_type = self.lexer_type + return ParsingFrontend(lexer_conf, parser_conf, options) + + def deserialize(self, data, memo, lexer_conf, callbacks, options): + parser_conf = ParserConf.deserialize(data['parser_conf'], memo) + parser = LALR_Parser.deserialize(data['parser'], memo, callbacks, options.debug) + parser_conf.callbacks = callbacks + return ParsingFrontend(lexer_conf, parser_conf, options, parser=parser) + + + + +class ParsingFrontend(Serialize): + __serialize_fields__ = 'lexer_conf', 'parser_conf', 'parser', 'options' + + def __init__(self, lexer_conf, parser_conf, options, parser=None): + self.parser_conf = parser_conf + self.lexer_conf = lexer_conf + self.options = options + + # Set-up parser + if parser: # From cache + self.parser = parser + else: + create_parser = { + 'lalr': create_lalr_parser, + 'earley': create_earley_parser, + 'cyk': CYK_FrontEnd, + }[parser_conf.parser_type] + self.parser = create_parser(lexer_conf, parser_conf, options) + + # Set-up lexer + lexer_type = lexer_conf.lexer_type + self.skip_lexer = False + if lexer_type in ('dynamic', 'dynamic_complete'): + assert lexer_conf.postlex is None + self.skip_lexer = True + return + + try: + create_lexer = { + 'standard': create_traditional_lexer, + 'contextual': create_contextual_lexer, + }[lexer_type] + except KeyError: + assert issubclass(lexer_type, Lexer), lexer_type + self.lexer = _wrap_lexer(lexer_type)(lexer_conf) + else: + self.lexer = create_lexer(lexer_conf, self.parser, lexer_conf.postlex) + + if lexer_conf.postlex: + self.lexer = PostLexConnector(self.lexer, lexer_conf.postlex) + + def _verify_start(self, start=None): + if start is None: + start_decls = self.parser_conf.start + if len(start_decls) > 1: + raise ConfigurationError("Lark initialized with more than 1 possible start rule. Must specify which start rule to parse", start_decls) + start ,= start_decls + elif start not in self.parser_conf.start: + raise ConfigurationError("Unknown start rule %s. Must be one of %r" % (start, self.parser_conf.start)) + return start + + def parse(self, text, start=None, on_error=None): + chosen_start = self._verify_start(start) + stream = text if self.skip_lexer else LexerThread(self.lexer, text) + kw = {} if on_error is None else {'on_error': on_error} + return self.parser.parse(stream, chosen_start, **kw) + + def parse_interactive(self, text=None, start=None): + chosen_start = self._verify_start(start) + if self.parser_conf.parser_type != 'lalr': + raise ConfigurationError("parse_interactive() currently only works with parser='lalr' ") + stream = text if self.skip_lexer else LexerThread(self.lexer, text) + return self.parser.parse_interactive(stream, chosen_start) + + +def get_frontend(parser, lexer): + assert_config(parser, ('lalr', 'earley', 'cyk')) + if not isinstance(lexer, type): # not custom lexer? + expected = { + 'lalr': ('standard', 'contextual'), + 'earley': ('standard', 'dynamic', 'dynamic_complete'), + 'cyk': ('standard', ), + }[parser] + assert_config(lexer, expected, 'Parser %r does not support lexer %%r, expected one of %%s' % parser) + + return MakeParsingFrontend(parser, lexer) + + +def _get_lexer_callbacks(transformer, terminals): + result = {} + for terminal in terminals: + callback = getattr(transformer, terminal.name, None) + if callback is not None: + result[terminal.name] = callback + return result + +class PostLexConnector: + def __init__(self, lexer, postlexer): + self.lexer = lexer + self.postlexer = postlexer + + def make_lexer_state(self, text): + return self.lexer.make_lexer_state(text) + + def lex(self, lexer_state, parser_state): + i = self.lexer.lex(lexer_state, parser_state) + return self.postlexer.process(i) + + + +def create_traditional_lexer(lexer_conf, parser, postlex): + return TraditionalLexer(lexer_conf) + +def create_contextual_lexer(lexer_conf, parser, postlex): + states = {idx:list(t.keys()) for idx, t in parser._parse_table.states.items()} + always_accept = postlex.always_accept if postlex else () + return ContextualLexer(lexer_conf, states, always_accept=always_accept) + +def create_lalr_parser(lexer_conf, parser_conf, options=None): + debug = options.debug if options else False + return LALR_Parser(parser_conf, debug=debug) + + +create_earley_parser = NotImplemented +CYK_FrontEnd = NotImplemented +###} + +class EarleyRegexpMatcher: + def __init__(self, lexer_conf): + self.regexps = {} + for t in lexer_conf.terminals: + if t.priority != 1: + raise GrammarError("Dynamic Earley doesn't support weights on terminals", t, t.priority) + regexp = t.pattern.to_regexp() + try: + width = get_regexp_width(regexp)[0] + except ValueError: + raise GrammarError("Bad regexp in token %s: %s" % (t.name, regexp)) + else: + if width == 0: + raise GrammarError("Dynamic Earley doesn't allow zero-width regexps", t) + if lexer_conf.use_bytes: + regexp = regexp.encode('utf-8') + + self.regexps[t.name] = lexer_conf.re_module.compile(regexp, lexer_conf.g_regex_flags) + + def match(self, term, text, index=0): + return self.regexps[term.name].match(text, index) + + +def create_earley_parser__dynamic(lexer_conf, parser_conf, options=None, **kw): + earley_matcher = EarleyRegexpMatcher(lexer_conf) + return xearley.Parser(parser_conf, earley_matcher.match, ignore=lexer_conf.ignore, **kw) + +def _match_earley_basic(term, token): + return term.name == token.type + +def create_earley_parser__basic(lexer_conf, parser_conf, options, **kw): + return earley.Parser(parser_conf, _match_earley_basic, **kw) + +def create_earley_parser(lexer_conf, parser_conf, options): + resolve_ambiguity = options.ambiguity == 'resolve' + debug = options.debug if options else False + tree_class = options.tree_class or Tree if options.ambiguity != 'forest' else None + + extra = {} + if lexer_conf.lexer_type == 'dynamic': + f = create_earley_parser__dynamic + elif lexer_conf.lexer_type == 'dynamic_complete': + extra['complete_lex'] =True + f = create_earley_parser__dynamic + else: + f = create_earley_parser__basic + + return f(lexer_conf, parser_conf, options, resolve_ambiguity=resolve_ambiguity, debug=debug, tree_class=tree_class, **extra) + + + +class CYK_FrontEnd: + def __init__(self, lexer_conf, parser_conf, options=None): + self._analysis = GrammarAnalyzer(parser_conf) + self.parser = cyk.Parser(parser_conf.rules) + + self.callbacks = parser_conf.callbacks + + def parse(self, lexer_thread, start): + tokens = list(lexer_thread.lex(None)) + tree = self.parser.parse(tokens, start) + return self._transform(tree) + + def _transform(self, tree): + subtrees = list(tree.iter_subtrees()) + for subtree in subtrees: + subtree.children = [self._apply_callback(c) if isinstance(c, Tree) else c for c in subtree.children] + + return self._apply_callback(tree) + + def _apply_callback(self, tree): + return self.callbacks[tree.rule](tree.children) |