--- /dev/null
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+from collections import MutableMapping
+try:
+ from thread import get_ident
+except ImportError:
+ try:
+ from _thread import get_ident
+ except ImportError:
+ from _dummy_thread import get_ident
+
+# from reprlib 3.2.1
+def recursive_repr(fillvalue=u'...'):
+ u'Decorator to make a repr function return fillvalue for a recursive call'
+
+ def decorating_function(user_function):
+ repr_running = set()
+
+ def wrapper(self):
+ key = id(self), get_ident()
+ if key in repr_running:
+ return fillvalue
+ repr_running.add(key)
+ try:
+ result = user_function(self)
+ finally:
+ repr_running.discard(key)
+ return result
+
+ # Can't use functools.wraps() here because of bootstrap issues
+ wrapper.__module__ = getattr(user_function, u'__module__')
+ wrapper.__doc__ = getattr(user_function, u'__doc__')
+ wrapper.__name__ = getattr(user_function, u'__name__')
+ wrapper.__annotations__ = getattr(user_function, u'__annotations__', {})
+ return wrapper
+
+ return decorating_function
+
+# from collections 3.2.1
+class _ChainMap(MutableMapping):
+ u''' A ChainMap groups multiple dicts (or other mappings) together
+ to create a single, updateable view.
+
+ The underlying mappings are stored in a list. That list is public and can
+ accessed or updated using the *maps* attribute. There is no other state.
+
+ Lookups search the underlying mappings successively until a key is found.
+ In contrast, writes, updates, and deletions only operate on the first
+ mapping.
+
+ '''
+
+ def __init__(self, *maps):
+ u'''Initialize a ChainMap by setting *maps* to the given mappings.
+ If no mappings are provided, a single empty dictionary is used.
+
+ '''
+ self.maps = list(maps) or [{}] # always at least one map
+
+ def __missing__(self, key):
+ raise KeyError(key)
+
+ def __getitem__(self, key):
+ for mapping in self.maps:
+ try:
+ return mapping[key] # can't use 'key in mapping' with defaultdict
+ except KeyError:
+ pass
+ return self.__missing__(key) # support subclasses that define __missing__
+
+ def get(self, key, default=None):
+ return self[key] if key in self else default
+
+ def __len__(self):
+ return len(set().union(*self.maps)) # reuses stored hash values if possible
+
+ def __iter__(self):
+ return iter(set().union(*self.maps))
+
+ def __contains__(self, key):
+ return any(key in m for m in self.maps)
+
+ @recursive_repr()
+ def __repr__(self):
+ return u'{0.__class__.__name__}({1})'.format(
+ self, u', '.join(map(repr, self.maps)))
+
+ @classmethod
+ def fromkeys(cls, iterable, *args):
+ u'Create a ChainMap with a single dict created from the iterable.'
+ return cls(dict.fromkeys(iterable, *args))
+
+ def copy(self):
+ u'New ChainMap or subclass with a new copy of maps[0] and refs to maps[1:]'
+ return self.__class__(self.maps[0].copy(), *self.maps[1:])
+
+ __copy__ = copy
+
+ def new_child(self): # like Django's Context.push()
+ u'New ChainMap with a new dict followed by all previous maps.'
+ return self.__class__({}, *self.maps)
+
+ @property
+ def parents(self): # like Django's Context.pop()
+ u'New ChainMap from maps[1:].'
+ return self.__class__(*self.maps[1:])
+
+ def __setitem__(self, key, value):
+ self.maps[0][key] = value
+
+ def __delitem__(self, key):
+ try:
+ del self.maps[0][key]
+ except KeyError:
+ raise KeyError(u'Key not found in the first mapping: {!r}'.format(key))
+
+ def popitem(self):
+ u'Remove and return an item pair from maps[0]. Raise KeyError is maps[0] is empty.'
+ try:
+ return self.maps[0].popitem()
+ except KeyError:
+ raise KeyError(u'No keys found in the first mapping.')
+
+ def pop(self, key, *args):
+ u'Remove *key* from maps[0] and return its value. Raise KeyError if *key* not in maps[0].'
+ try:
+ return self.maps[0].pop(key, *args)
+ except KeyError:
+ raise KeyError(u'Key not found in the first mapping: {!r}'.format(key))
+
+ def clear(self):
+ u'Clear maps[0], leaving maps[1:] intact.'
+ self.maps[0].clear()
projects / iramuteq / blobdiff