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Date: Wed, 29 May 2013 12:46:19 -0500
Subject: Getting a callable for any value?
From: Croepha <croepha@gmail.com>
To: python-list@python.org
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Is there anything like this in the standard library?

class AnyFactory(object):
def __init__(self, anything):
self.product = anything
def __call__(self):
return self.product
def __repr__(self):
return "%s.%s(%r)" % (self.__class__.__module__, self.__class__.__name__,
self.product)

my use case is:
collections.defaultdict(AnyFactory(collections.defaultdict(AnyFactory(None))))

And I think lambda expressions are not preferable...

I found itertools.repeat(anything).next and functools.partial(copy.copy,
anything)

but both of those don't repr well... and are confusing...

I think AnyFactory is the most readable, but is confusing if the reader
doesn't know what it is, am I missing a standard implementation of this?

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<div dir=3D"ltr">Is there anything like this in the standard library?<div><=
br></div><div><div>class AnyFactory(object):</div><div><span class=3D"" sty=
le=3D"white-space:pre">	</span>def __init__(self, anything):</div><div><spa=
n class=3D"" style=3D"white-space:pre">		</span>self.product =3D anything</=
div>
<div><span class=3D"" style=3D"white-space:pre">	</span>def __call__(self):=
</div><div><span class=3D"" style=3D"white-space:pre">		</span>return self.=
product</div><div><span class=3D"" style=3D"white-space:pre">	</span>def __=
repr__(self):</div>
<div><span class=3D"" style=3D"white-space:pre">		</span>return &quot;%s.%s=
(%r)&quot; % (self.__class__.__module__, self.__class__.__name__, self.prod=
uct)</div></div><div><br></div><div style>my use case is: collections.defau=
ltdict(AnyFactory(collections.defaultdict(AnyFactory(None))))</div>
<div style><br></div><div style>And I think lambda expressions are not=C2=
=A0preferable...</div><div style><br></div><div style>I found itertools.rep=
eat(anything).next and functools.partial(copy.copy, anything)</div><div sty=
le>
<br></div><div style>but both of those don&#39;t repr well... and are confu=
sing... =C2=A0</div><div style><br></div><div style>I think AnyFactory is t=
he most readable, but is confusing if the reader doesn&#39;t know what it i=
s, am I missing a standard implementation of this?</div>
<div style><br></div></div>

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