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- Committer: Necoro
- Date: 2008-03-24 22:05:07 UTC
- Revision ID: svn-v3-trunk0:707e4503-1661-43cb-8fc9-483266be2d6d:tags%2F0.8.6.2:686
Moved versions back to tags
- files added:
- doc
- etc
- i18n
- icons
- plugins
- portato
- portato/backend
- portato/backend/catapult
- portato/backend/portage
- portato/gui
- portato/gui/gtk
- portato/gui/templates
- portato/plugins
- shm
added
removed
portato/config_parser.py
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# -*- coding: utf-8 -*-
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#
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# File: portato/config_parser.py
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# This file is part of the Portato-Project, a graphical portage-frontend.
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#
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# Copyright (C) 2006-2007 René 'Necoro' Neumann
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# This is free software. You may redistribute copies of it under the terms of
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# the GNU General Public License version 2.
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# There is NO WARRANTY, to the extent permitted by law.
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#
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# Written by René 'Necoro' Neumann <necoro@necoro.net>
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"""A simple parser for configuration files in ini-style.
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The main difference to other simple ini-parsers is, that it does not
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write the whole structure into the file, but only the changed values.
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Thus it keeps comments and structuring of the file.
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@var DELIMITER: list of delimiters allowed
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@type DELIMITER: string[]
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@var COMMENT: comment marks allowed
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@type COMMENT: string[]
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@var TRUE: Regular expression for all TRUE values allowed.
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Currently supported are the values (case insensitive): true, 1, on, wahr, ja, yes.
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@var FALSE: Regular expression for all FALSE values allowed.
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Currently supported are the values (case insensitive): false, 0, off, falsch, nein, no,
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@var SECTION: Regular expression allowing the recognition of a section header.
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@var EXPRESSION: Regular expression defining a normal option-value pair.
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"""
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from __future__ import absolute_import
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import re
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from gettext import lgettext as _
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from .helper import debug
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DELIMITER = ["=", ":"]
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COMMENT = [";","#"]
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# precompiled expressions
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TRUE = re.compile("((true)|(1)|(on)|(wahr)|(ja)|(yes))", re.I)
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FALSE = re.compile("((false)|(0)|(off)|(falsch)|(nein)|(no))", re.I)
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SECTION = re.compile("\s*\[(\w+)\]\s*")
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EXPRESSION = re.compile(r"\s*(\w+)\s*[:=]\s*(.*)\s*")
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class Value (object):
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"""Class defining a value of a key.
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@ivar value: The specific value. This is a property.
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@type value: arbitrary
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@ivar line: The line in the config file.
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@type line: int
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@ivar boolean: The boolean meaning of this value. Set this to C{None} if this is not a boolean.
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@type boolean: boolean
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@ivar changed: Set to True if the value has been changed.
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@type changed: boolean
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@ivar old: The old value.
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@type old: arbitrary"""
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def __init__ (self, value, line, bool = None):
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"""Constructor.
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@param value: the value
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@type value: string
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@param line: the line in the config file
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@type line: int
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@param bool: The boolean meaning of the value. Set this to C{None} if this is not a boolean.
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@type bool: boolean"""
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self.__value = value
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self.line = line
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self.boolean = bool
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self.changed = False # true if we changed it
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self.old = value # keep the original one ... so if we change it back to this one, we do not have to write
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def set (self, value):
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"""Sets the value to a new one.
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@param value: new value
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@type value: string"""
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self.__value = value
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if value != self.old:
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self.changed = True
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else:
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self.changed = False
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def get (self):
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"""Returns the actual value.
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@returns: the actual value
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@rtype: string"""
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return self.__value
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def is_bool (self):
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"""Returns whether the actual value has a boolean meaning.
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@returns: True if the actual value can be interpreted as a boolean
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@rtype: boolean"""
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return (self.boolean != None)
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def __str__ (self):
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return str(self.__value)
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def __repr__ (self):
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return self.__str__()
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value = property(get,set)
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class ConfigParser:
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"""The parser class.
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@cvar true_false: A mapping from the truth values to their opposits.
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@type true_false: string -> string
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@ivar file: the file to scan
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@type file: string
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@ivar cache: caches the content of the file
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@type cache: string[]
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@ivar vars: the found options grouped by section
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@type vars: string -> (string -> L{Value})
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@ivar pos: the positions of the values grouped by lineno
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@type pos: int -> (int, int)"""
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# generates the complementary true-false-pairs
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true_false = {
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"true" : "false",
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"1" : "0",
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"on" : "off",
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"yes" : "no",
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"ja" : "nein",
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"wahr" : "falsch"}
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true_false.update(zip(true_false.values(), true_false.keys()))
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def __init__ (self, file):
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"""Constructor.
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@param file: the configuration file to open
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@type file: string"""
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self.file = file
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self.__initialize()
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def __initialize (self):
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"""Private method which initializes our dictionaries."""
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self.vars = {"MAIN": {}}
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self.cache = None # file cache
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self.pos = {} # stores the positions of the matches
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def _invert (self, val):
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"""Invertes a given boolean.
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@param val: value to invert
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@type val: string
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@returns: inverted value
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@rtype: string"""
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return self.true_false[val.lower()]
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def parse (self):
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"""Parses the file."""
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# read into cache
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file = open(self.file, "r")
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self.cache = file.readlines()
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file.close()
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# implicit first section is main
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section = "MAIN"
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count = -1
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for line in self.cache:
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count += 1
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ls = line.strip()
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if not ls: continue # empty
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if ls[0] in COMMENT: continue # comment
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# look for a section
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match = SECTION.search(line)
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if match:
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sec = match.group(1).upper()
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if sec != section:
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self.vars[sec] = {}
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section = sec
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continue
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# look for an expression
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match = EXPRESSION.search(line)
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if match:
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val = match.group(2)
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# find the boolean value
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bool = None
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if TRUE.match(val):
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bool = True
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elif FALSE.match(val):
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bool = False
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# insert
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key = match.group(1).lower()
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self.vars[section][key] = Value(val, count, bool = bool)
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self.pos[count] = match.span(2)
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else: # neither comment nor empty nor expression nor section => error
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error(_("Unrecognized line in configuration: %s"), line)
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def get (self, key, section = "MAIN"):
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"""Returns the value of a given key in a section.
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@param key: the key
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@type key: string
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@param section: the section
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@type section: string
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@returns: value
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@rtype: string
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@raises KeyError: if section or key could not be found"""
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section = section.upper()
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key = key.lower()
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return self.vars[section][key].value
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def get_boolean (self, key, section = "MAIN"):
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"""Returns the boolean value of a given key in a section.
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@param key: the key
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@type key: string
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@param section: the section
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@type section: string
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@returns: value
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@rtype: boolean
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@raises KeyError: if section or key could not be found
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@raises ValueError: if key does not have a boolean value"""
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section = section.upper()
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key = key.lower()
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val = self.vars[section][key]
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if val.is_bool():
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return val.boolean
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raise ValueError, "\"%s\" is not a boolean." % key
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def set (self, key, value = "", section = "MAIN"):
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"""Sets a new value of a given key in a section.
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@param key: the key
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@type key: string
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@param value: the new value
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@type value: string
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@param section: the section
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@type section: string
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@raises KeyError: if section or key could not be found"""
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section = section.upper()
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key = key.lower()
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self.vars[section][key].value = value
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def set_boolean (self, key, value, section = "MAIN"):
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"""Sets a new boolean value of a given key in a section.
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Therefore it invertes the string representation of the boolean (in lowercase).
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@param key: the key
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@type key: string
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@param value: the new value
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@type value: boolean
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@param section: the section
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@type section: string
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@raises KeyError: if section or key could not be found
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@raises ValueError: if the old/new value is not a boolean"""
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section = section.upper()
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key = key.lower()
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if not isinstance(value, bool):
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raise ValueError, "Passed value must be a boolean."
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val = self.vars[section][key]
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if val.is_bool():
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if value is not val.boolean:
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val.boolean = value
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val.value = self._invert(val.value)
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else:
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raise ValueError, "\"%s\" is not a boolean." % key
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def write (self):
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"""Writes file."""
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for sec in self.vars:
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for key in self.vars[sec]:
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val = self.vars[sec][key]
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if val.changed:
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part1 = self.cache[val.line][:self.pos[val.line][0]] # key+DELIMITER
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part2 = val.value # value
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part3 = self.cache[val.line][self.pos[val.line][1]:] # everything behind the vale (\n in normal cases)
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self.cache[val.line] = part1 + part2 + part3
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# write
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f = open(self.file, "w")
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f.writelines(self.cache)
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f.close()
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# reload
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self.__initialize()
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self.parse()
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