Right now, an example for single dispatch would be:
from functools import singledispatch
@singledispatch
def fun(arg, verbose=True):
if verbose:
print("Let me just say,", end=" ")
print(arg)
@fun.register(int)
def _(arg, verbose=True):
if verbose:
print("Strength in numbers, eh?", end=" ")
print(arg)
@fun.register(list)
def _(arg, verbose=True):
if verbose:
print("Enumerate this:")
for i, elem in enumerate(arg):
print(i, elem)
But this makes a useless _ function, that should either be deleted or
ignored. For properties, a common pattern is this:
class Foo:
@property
def bar(self):
return self._bar
@bar.setter
def bar(self, value):
self._bar = value
So I'm suggesting that @function.register for single dispatch
functions returns the same function, so you would end up with
something like:
@singledispatch
def fun(arg, verbose=True):
if verbose:
print("Let me just say,", end=" ")
print(arg)
@fun.register(int)
def fun(arg, verbose=True):
if verbose:
print("Strength in numbers, eh?", end=" ")
print(arg)
And to get back the old behaviour, where you can get the function
being decorated, just call it afterwards:
@singledispatch
def fun(arg, verbose=True):
if verbose:
print("Let me just say,", end=" ")
print(arg)
def used_elsewhere(arg, verbose=True):
if verbose:
print("Strength in numbers, eh?", end=" ")
print(arg)
fun.register(int)(used_elsewhere)
But this goes against what a single-dispatch function is, so I think
this is a minor enough use case to not worry about.
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