Adds a key= argument to min and max modeled after that of list.sort and sorted.
These will become obsolete in Python 2.5. when the builtin min() and max() functions gain the key= argument.
Python, 17 lines
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Copy to clipboard1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 | class _minmax(object):
def __init__(self, func):
self.func = func
def __call__(self, *seq, **kwargs):
key = kwargs.pop('key', None)
if kwargs:
raise TypeError("only 'key' accepted as a "
"keyword argument")
if key is None:
return self.func(*seq)
if len(seq) == 1:
seq, = seq
return self.func((key(item), i, item)
for i, item in enumerate(seq))[-1]
min = _minmax(min)
max = _minmax(max)
|
Raymond Hettinger previously posted a similar recipe: http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/355690
This implementation augments the functionality of Raymond Hettinger's recipe, supporting both argument forms accepted by the current builtin min and max: a single sequence and *args list. As will be true in Python 2.5, 'key' is only accepted as a keyword argument (never as a positional one). <pre>py> min('ab', 'c') 'ab' py> min('ab', 'c', key=len) 'c' py> d = dict(a=2, b=1) py> max(d) 'b' py> max(d, key=d.__getitem__) 'a'</pre>
