-#!/usr/bin/env python
-# -*- coding: utf-8 -*-
+#! /usr/bin/env python
-# CAVEAT UTILITOR
-#
-# This file was automatically generated by Grako.
-#
-# https://pypi.python.org/pypi/grako/
-#
-# Any changes you make to it will be overwritten the next time
-# the file is generated.
+import os
+from lark import Lark, Transformer
-from __future__ import print_function, division, absolute_import, unicode_literals
+class TagsTransformer(Transformer):
+ def and_expression(self, items):
+ left = items[0]
+ right = items[2]
+ if len(items) > 3:
+ right = self.and_expression(items[2:])
+ return ('AND', left, right)
-from grako.parsing import graken, Parser
-from grako.util import re, RE_FLAGS, generic_main # noqa
+ def or_expression(self, items):
+ left = items[0]
+ right = items[2]
+ if len(items) > 3:
+ right = self.or_expression(items[2:])
+ return ('OR', left, right)
+ def not_expression(self, items):
+ return ('NOT', items[1])
-__version__ = (2016, 7, 9, 18, 10, 4, 5)
+ def expression_parens(self, items):
+ return ('PARENS', items[0])
-__all__ = [
- 'TagsParser',
- 'TagsSemantics',
- 'main'
-]
+ def name(self, name):
+ return ('NAME', name[0].value)
-KEYWORDS = set([])
+# cache
+_grammar = None
-class TagsParser(Parser):
- def __init__(self,
- whitespace=None,
- nameguard=None,
- comments_re=None,
- eol_comments_re=None,
- ignorecase=None,
- left_recursion=True,
- keywords=KEYWORDS,
- namechars='',
- **kwargs):
- super(TagsParser, self).__init__(
- whitespace=whitespace,
- nameguard=nameguard,
- comments_re=comments_re,
- eol_comments_re=eol_comments_re,
- ignorecase=ignorecase,
- left_recursion=left_recursion,
- keywords=keywords,
- namechars=namechars,
- **kwargs
- )
- @graken()
- def _start_(self):
- self._expression_()
- self._check_eof()
+def load_grammar():
+ global _grammar
+ parser_dir = os.path.dirname(__file__)
+ with open(os.path.join(parser_dir, 'grammar.ebnf'), 'rt') as grammar_file:
+ grammar_text = grammar_file.read()
+ grammar_lines = [line for line in grammar_text.splitlines()
+ if not line.startswith('#')]
+ grammar_text = '\n'.join(grammar_lines)
+ _grammar = Lark(grammar_text)
- @graken()
- def _expression_(self):
- with self._group():
- with self._choice():
- with self._option():
- self._expression_()
- self._and_op_()
- self._expression_()
- with self._option():
- self._expression_()
- self._or_op_()
- self._expression_()
- with self._option():
- self._not_op_()
- self._expression_()
- with self._option():
- self._expression_parens_()
- with self._option():
- self._name_()
- self._error('no available options')
- @graken()
- def _expression_parens_(self):
- self._token('(')
- self._expression_()
- self._token(')')
+def parse(input):
+ if _grammar is None:
+ load_grammar()
+ tree = _grammar.parse(input)
+ return TagsTransformer().transform(tree)
- @graken()
- def _name_(self):
- self._pattern(r'[a-z][a-z0-9_]+')
-
- @graken()
- def _and_op_(self):
- with self._choice():
- with self._option():
- self._token('&')
- with self._option():
- self._token('&&')
- with self._option():
- self._token('AND')
- with self._option():
- self._token('and')
- self._error('expecting one of: & && AND and')
-
- @graken()
- def _or_op_(self):
- with self._choice():
- with self._option():
- self._token('|')
- with self._option():
- self._token('||')
- with self._option():
- self._token('OR')
- with self._option():
- self._token('or')
- self._error('expecting one of: OR or | ||')
-
- @graken()
- def _not_op_(self):
- with self._choice():
- with self._option():
- self._token('!')
- with self._option():
- self._token('NOT')
- with self._option():
- self._token('not')
- self._error('expecting one of: ! NOT not')
-
-
-class TagsSemantics(object):
- def start(self, ast):
- return ast
-
- def expression(self, ast):
- return ast
-
- def expression_parens(self, ast):
- return ast
-
- def name(self, ast):
- return ast
-
- def and_op(self, ast):
- return ast
-
- def or_op(self, ast):
- return ast
-
- def not_op(self, ast):
- return ast
-
-
-def main(
- filename,
- startrule,
- trace=False,
- whitespace=None,
- nameguard=None,
- comments_re=None,
- eol_comments_re=None,
- ignorecase=None,
- left_recursion=True,
- **kwargs):
-
- with open(filename) as f:
- text = f.read()
- whitespace = whitespace or None
- parser = TagsParser(parseinfo=False)
- ast = parser.parse(
- text,
- startrule,
- filename=filename,
- trace=trace,
- whitespace=whitespace,
- nameguard=nameguard,
- ignorecase=ignorecase,
- **kwargs)
- return ast
if __name__ == '__main__':
- import json
- ast = generic_main(main, TagsParser, name='Tags')
- print('AST:')
- print(ast)
- print()
- print('JSON:')
- print(json.dumps(ast, indent=2))
- print()
+ print '----------'
+ print parse('test')
+ print parse('!test')
+ print parse('not test')
+ print parse('foo or bar')
+ print parse('foo && bar')
+ print parse('foo && bar && baz')
+ print parse('!foo && bar && baz')
+ print parse('(test)')
+ print parse('(foo || bar)')
+ print parse('(foo and !bar)')
+ print '----------'
projects / phdru.name / cgi-bin / blog-ru / search-tags.git / blobdiff