diff --git a/lib/assets/Lib/functools.py b/lib/assets/Lib/functools.py new file mode 100644 --- /dev/null +++ b/lib/assets/Lib/functools.py @@ -0,0 +1,331 @@ +"""functools.py - Tools for working with functions and callable objects +""" +# Python module wrapper for _functools C module +# to allow utilities written in Python to be added +# to the functools module. +# Written by Nick Coghlan +# and Raymond Hettinger +# Copyright (C) 2006-2010 Python Software Foundation. +# See C source code for _functools credits/copyright + +__all__ = ['update_wrapper', 'wraps', 'WRAPPER_ASSIGNMENTS', 'WRAPPER_UPDATES', + 'total_ordering', 'cmp_to_key', 'lru_cache', 'reduce', 'partial'] + +from _functools import partial, reduce +from collections import namedtuple +try: + from _thread import RLock +except: + class RLock: + 'Dummy reentrant lock for builds without threads' + def __enter__(self): pass + def __exit__(self, exctype, excinst, exctb): pass + + +################################################################################ +### update_wrapper() and wraps() decorator +################################################################################ + +# update_wrapper() and wraps() are tools to help write +# wrapper functions that can handle naive introspection + +WRAPPER_ASSIGNMENTS = ('__module__', '__name__', '__qualname__', '__doc__', + '__annotations__') +WRAPPER_UPDATES = ('__dict__',) +def update_wrapper(wrapper, + wrapped, + assigned = WRAPPER_ASSIGNMENTS, + updated = WRAPPER_UPDATES): + """Update a wrapper function to look like the wrapped function + + wrapper is the function to be updated + wrapped is the original function + assigned is a tuple naming the attributes assigned directly + from the wrapped function to the wrapper function (defaults to + functools.WRAPPER_ASSIGNMENTS) + updated is a tuple naming the attributes of the wrapper that + are updated with the corresponding attribute from the wrapped + function (defaults to functools.WRAPPER_UPDATES) + """ + wrapper.__wrapped__ = wrapped + for attr in assigned: + try: + value = getattr(wrapped, attr) + except AttributeError: + pass + else: + setattr(wrapper, attr, value) + for attr in updated: + getattr(wrapper, attr).update(getattr(wrapped, attr, {})) + # Return the wrapper so this can be used as a decorator via partial() + return wrapper + +def wraps(wrapped, + assigned = WRAPPER_ASSIGNMENTS, + updated = WRAPPER_UPDATES): + """Decorator factory to apply update_wrapper() to a wrapper function + + Returns a decorator that invokes update_wrapper() with the decorated + function as the wrapper argument and the arguments to wraps() as the + remaining arguments. Default arguments are as for update_wrapper(). + This is a convenience function to simplify applying partial() to + update_wrapper(). + """ + return partial(update_wrapper, wrapped=wrapped, + assigned=assigned, updated=updated) + + +################################################################################ +### total_ordering class decorator +################################################################################ + +def total_ordering(cls): + """Class decorator that fills in missing ordering methods""" + convert = { + '__lt__': [('__gt__', lambda self, other: not (self < other or self == other)), + ('__le__', lambda self, other: self < other or self == other), + ('__ge__', lambda self, other: not self < other)], + '__le__': [('__ge__', lambda self, other: not self <= other or self == other), + ('__lt__', lambda self, other: self <= other and not self == other), + ('__gt__', lambda self, other: not self <= other)], + '__gt__': [('__lt__', lambda self, other: not (self > other or self == other)), + ('__ge__', lambda self, other: self > other or self == other), + ('__le__', lambda self, other: not self > other)], + '__ge__': [('__le__', lambda self, other: (not self >= other) or self == other), + ('__gt__', lambda self, other: self >= other and not self == other), + ('__lt__', lambda self, other: not self >= other)] + } + # Find user-defined comparisons (not those inherited from object). + roots = [op for op in convert if getattr(cls, op, None) is not getattr(object, op, None)] + if not roots: + raise ValueError('must define at least one ordering operation: < > <= >=') + root = max(roots) # prefer __lt__ to __le__ to __gt__ to __ge__ + for opname, opfunc in convert[root]: + if opname not in roots: + opfunc.__name__ = opname + opfunc.__doc__ = getattr(int, opname).__doc__ + setattr(cls, opname, opfunc) + return cls + + +################################################################################ +### cmp_to_key() function converter +################################################################################ + +def cmp_to_key(mycmp): + """Convert a cmp= function into a key= function""" + class K(object): + __slots__ = ['obj'] + def __init__(self, obj): + self.obj = obj + def __lt__(self, other): + return mycmp(self.obj, other.obj) < 0 + def __gt__(self, other): + return mycmp(self.obj, other.obj) > 0 + def __eq__(self, other): + return mycmp(self.obj, other.obj) == 0 + def __le__(self, other): + return mycmp(self.obj, other.obj) <= 0 + def __ge__(self, other): + return mycmp(self.obj, other.obj) >= 0 + def __ne__(self, other): + return mycmp(self.obj, other.obj) != 0 + __hash__ = None + return K + +try: + from _functools import cmp_to_key +except ImportError: + pass + + +################################################################################ +### LRU Cache function decorator +################################################################################ + +_CacheInfo = namedtuple("CacheInfo", ["hits", "misses", "maxsize", "currsize"]) + +class _HashedSeq(list): + """ This class guarantees that hash() will be called no more than once + per element. This is important because the lru_cache() will hash + the key multiple times on a cache miss. + + """ + + __slots__ = 'hashvalue' + + def __init__(self, tup, hash=hash): + self[:] = tup + self.hashvalue = hash(tup) + + def __hash__(self): + return self.hashvalue + +def _make_key(args, kwds, typed, + kwd_mark = (object(),), + fasttypes = {int, str, frozenset, type(None)}, + sorted=sorted, tuple=tuple, type=type, len=len): + """Make a cache key from optionally typed positional and keyword arguments + + The key is constructed in a way that is flat as possible rather than + as a nested structure that would take more memory. + + If there is only a single argument and its data type is known to cache + its hash value, then that argument is returned without a wrapper. This + saves space and improves lookup speed. + + """ + key = args + if kwds: + sorted_items = sorted(kwds.items()) + key += kwd_mark + for item in sorted_items: + key += item + if typed: + key += tuple(type(v) for v in args) + if kwds: + key += tuple(type(v) for k, v in sorted_items) + elif len(key) == 1 and type(key[0]) in fasttypes: + return key[0] + return _HashedSeq(key) + +def lru_cache(maxsize=128, typed=False): + """Least-recently-used cache decorator. + + If *maxsize* is set to None, the LRU features are disabled and the cache + can grow without bound. + + If *typed* is True, arguments of different types will be cached separately. + For example, f(3.0) and f(3) will be treated as distinct calls with + distinct results. + + Arguments to the cached function must be hashable. + + View the cache statistics named tuple (hits, misses, maxsize, currsize) + with f.cache_info(). Clear the cache and statistics with f.cache_clear(). + Access the underlying function with f.__wrapped__. + + See: http://en.wikipedia.org/wiki/Cache_algorithms#Least_Recently_Used + + """ + + # Users should only access the lru_cache through its public API: + # cache_info, cache_clear, and f.__wrapped__ + # The internals of the lru_cache are encapsulated for thread safety and + # to allow the implementation to change (including a possible C version). + + # Constants shared by all lru cache instances: + sentinel = object() # unique object used to signal cache misses + make_key = _make_key # build a key from the function arguments + PREV, NEXT, KEY, RESULT = 0, 1, 2, 3 # names for the link fields + + def decorating_function(user_function): + + cache = {} + hits = misses = 0 + full = False + cache_get = cache.get # bound method to lookup a key or return None + lock = RLock() # because linkedlist updates aren't threadsafe + root = [] # root of the circular doubly linked list + root[:] = [root, root, None, None] # initialize by pointing to self + + if maxsize == 0: + + def wrapper(*args, **kwds): + # No caching -- just a statistics update after a successful call + nonlocal misses + result = user_function(*args, **kwds) + misses += 1 + return result + + elif maxsize is None: + + def wrapper(*args, **kwds): + # Simple caching without ordering or size limit + nonlocal hits, misses + key = make_key(args, kwds, typed) + result = cache_get(key, sentinel) + if result is not sentinel: + hits += 1 + return result + result = user_function(*args, **kwds) + cache[key] = result + misses += 1 + return result + + else: + + def wrapper(*args, **kwds): + # Size limited caching that tracks accesses by recency + nonlocal root, hits, misses, full + key = make_key(args, kwds, typed) + with lock: + link = cache_get(key) + if link is not None: + # Move the link to the front of the circular queue + link_prev, link_next, _key, result = link + link_prev[NEXT] = link_next + link_next[PREV] = link_prev + last = root[PREV] + last[NEXT] = root[PREV] = link + link[PREV] = last + link[NEXT] = root + hits += 1 + return result + result = user_function(*args, **kwds) + with lock: + if key in cache: + # Getting here means that this same key was added to the + # cache while the lock was released. Since the link + # update is already done, we need only return the + # computed result and update the count of misses. + pass + elif full: + # Use the old root to store the new key and result. + oldroot = root + oldroot[KEY] = key + oldroot[RESULT] = result + # Empty the oldest link and make it the new root. + # Keep a reference to the old key and old result to + # prevent their ref counts from going to zero during the + # update. That will prevent potentially arbitrary object + # clean-up code (i.e. __del__) from running while we're + # still adjusting the links. + root = oldroot[NEXT] + oldkey = root[KEY] + oldresult = root[RESULT] + root[KEY] = root[RESULT] = None + # Now update the cache dictionary. + del cache[oldkey] + # Save the potentially reentrant cache[key] assignment + # for last, after the root and links have been put in + # a consistent state. + cache[key] = oldroot + else: + # Put result in a new link at the front of the queue. + last = root[PREV] + link = [last, root, key, result] + last[NEXT] = root[PREV] = cache[key] = link + full = (len(cache) >= maxsize) + misses += 1 + return result + + def cache_info(): + """Report cache statistics""" + with lock: + return _CacheInfo(hits, misses, maxsize, len(cache)) + + def cache_clear(): + """Clear the cache and cache statistics""" + nonlocal hits, misses, full + with lock: + cache.clear() + root[:] = [root, root, None, None] + hits = misses = 0 + full = False + + wrapper.cache_info = cache_info + wrapper.cache_clear = cache_clear + return update_wrapper(wrapper, user_function) + + return decorating_function