summaryrefslogtreecommitdiff
path: root/lib/python2.7/functools.py
diff options
context:
space:
mode:
Diffstat (limited to 'lib/python2.7/functools.py')
-rw-r--r--lib/python2.7/functools.py100
1 files changed, 100 insertions, 0 deletions
diff --git a/lib/python2.7/functools.py b/lib/python2.7/functools.py
new file mode 100644
index 0000000..53680b8
--- /dev/null
+++ b/lib/python2.7/functools.py
@@ -0,0 +1,100 @@
+"""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 <ncoghlan at gmail.com>
+# Copyright (C) 2006 Python Software Foundation.
+# See C source code for _functools credits/copyright
+
+from _functools import partial, reduce
+
+# update_wrapper() and wraps() are tools to help write
+# wrapper functions that can handle naive introspection
+
+WRAPPER_ASSIGNMENTS = ('__module__', '__name__', '__doc__')
+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)
+ """
+ for attr in assigned:
+ setattr(wrapper, attr, getattr(wrapped, attr))
+ 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)
+
+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)]
+ }
+ roots = set(dir(cls)) & set(convert)
+ 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
+
+def cmp_to_key(mycmp):
+ """Convert a cmp= function into a key= function"""
+ class K(object):
+ __slots__ = ['obj']
+ def __init__(self, obj, *args):
+ 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
+ def __hash__(self):
+ raise TypeError('hash not implemented')
+ return K