diff options
Diffstat (limited to 'plugins/snippets/snippets/substitutionparser.py')
| -rw-r--r-- | plugins/snippets/snippets/substitutionparser.py | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/plugins/snippets/snippets/substitutionparser.py b/plugins/snippets/snippets/substitutionparser.py new file mode 100644 index 0000000..8469dd3 --- /dev/null +++ b/plugins/snippets/snippets/substitutionparser.py @@ -0,0 +1,203 @@ +# Gedit snippets plugin +# Copyright (C) 2006-2007 Jesse van den Kieboom <jesse@icecrew.nl> +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + +import re + +class ParseError(Exception): + def __str__(self): + return 'Parse error, resume next' + +class Modifiers: + def _first_char(s): + first = (s != '' and s[0]) or '' + rest = (len(s) > 1 and s[1:]) or '' + + return first, rest + + def upper_first(s): + first, rest = Modifiers._first_char(s) + + return '%s%s' % (first.upper(), rest) + + def upper(s): + return s.upper() + + def lower_first(s): + first, rest = Modifiers._first_char(s) + + return '%s%s' % (first.lower(), rest) + + def lower(s): + return s.lower() + + def title(s): + return s.title() + + upper_first = staticmethod(upper_first) + upper = staticmethod(upper) + lower_first = staticmethod(lower_first) + lower = staticmethod(lower) + title = staticmethod(title) + _first_char = staticmethod(_first_char) + +class SubstitutionParser: + REG_ID = '[0-9]+' + REG_NAME = '[a-zA-Z_]+' + REG_MOD = '[a-zA-Z]+' + REG_ESCAPE = '\\\\|\\(\\?|,|\\)' + + REG_GROUP = '(?:(%s)|<(%s|%s)(?:,(%s))?>)' % (REG_ID, REG_ID, REG_NAME, REG_MOD) + + def __init__(self, pattern, groups = {}, modifiers = {}): + self.pattern = pattern + self.groups = groups + + self.modifiers = {'u': Modifiers.upper_first, + 'U': Modifiers.upper, + 'l': Modifiers.lower_first, + 'L': Modifiers.lower, + 't': Modifiers.title} + + for k, v in modifiers.items(): + self.modifiers[k] = v + + def parse(self): + result, tokens = self._parse(self.pattern, None) + + return result + + def _parse(self, tokens, terminator): + result = '' + + while tokens != '': + if self._peek(tokens) == '' or self._peek(tokens) == terminator: + tokens = self._remains(tokens) + break + + try: + res, tokens = self._expr(tokens, terminator) + except ParseError: + res, tokens = self._text(tokens) + + result += res + + return result, tokens + + def _peek(self, tokens, num = 0): + return (num < len(tokens) and tokens[num]) + + def _token(self, tokens): + if tokens == '': + return '', ''; + + return tokens[0], (len(tokens) > 1 and tokens[1:]) or '' + + def _remains(self, tokens, num = 1): + return (num < len(tokens) and tokens[num:]) or '' + + def _expr(self, tokens, terminator): + if tokens == '': + return '' + + try: + return {'\\': self._escape, + '(': self._condition}[self._peek(tokens)](tokens, terminator) + except KeyError: + raise ParseError + + def _text(self, tokens): + return self._token(tokens) + + def _substitute(self, group, modifiers = ''): + result = (self.groups.has_key(group) and self.groups[group]) or '' + + for modifier in modifiers: + if self.modifiers.has_key(modifier): + result = self.modifiers[modifier](result) + + return result + + def _match_group(self, tokens): + match = re.match('\\\\%s' % self.REG_GROUP, tokens) + + if not match: + return None, tokens + + return self._substitute(match.group(1) or match.group(2), match.group(3) or ''), tokens[match.end():] + + def _escape(self, tokens, terminator): + # Try to match a group + result, tokens = self._match_group(tokens) + + if result != None: + return result, tokens + + s = self.REG_GROUP + + if terminator: + s += '|%s' % re.escape(terminator) + + match = re.match('\\\\(\\\\%s|%s)' % (s, self.REG_ESCAPE), tokens) + + if not match: + raise ParseError + + return match.group(1), tokens[match.end():] + + def _condition_value(self, tokens): + match = re.match('\\\\?%s\s*' % self.REG_GROUP, tokens) + + if not match: + return None, tokens + + groups = match.groups() + name = groups[0] or groups[1] + + return self.groups.has_key(name) and self.groups[name] != None, tokens[match.end():] + + def _condition(self, tokens, terminator): + # Match ? after ( + if self._peek(tokens, 1) != '?': + raise ParseError + + # Remove initial (? token + tokens = self._remains(tokens, 2) + condition, tokens = self._condition_value(tokens) + + if condition is None or self._peek(tokens) != ',': + raise ParseError + + truepart, tokens = self._parse(self._remains(tokens), ',') + + if truepart is None: + raise ParseError + + falsepart, tokens = self._parse(tokens, ')') + + if falsepart is None: + raise ParseError + + if condition: + return truepart, tokens + else: + return falsepart, tokens + + @staticmethod + def escape_substitution(substitution): + return re.sub('(%s|%s)' % (SubstitutionParser.REG_GROUP, SubstitutionParser.REG_ESCAPE), '\\\\\\1', substitution) + +# ex:ts=4:et: |