mk a écrit :
Bruno Desthuilliers wrote:
(snip)
class Foo2(object):
""" naive solution : kinda work, BUT will fail
with the real code that has plain functions
in 'tagada'
"""
@staticmethod
def bar(baaz):
print baaz
tagada = {'bar': bar}
def test(self, baaz):
self.tagada['bar'].__get__(self)(baaz)
Well I could always do:
if isinstance(self.tagada['bar'], staticmethod):
self.tagada['bar'].__get__(self)(baaz)
else:
self.tagada['bar'](baaz)
But 1. this apparently defeats the purpose of using print_internal_date
on instance/class in 'normal' way, and 2. I probably shouldn't be doing
that since using isinstance is apparently like playing with yourself:
while technically legal, people look at you weirdly. :-)
As far as I'm concerned, this would be a valid use case for isinstance.
But it breaks uniformity and requires quite a lot of mostly useless code.
class Foo3(object):
""" working solution 1 : defer the wrapping
of 'bar' as a staticmethod
"""
def bar(baaz):
print baaz
tagada = {'bar': bar}
bar = staticmethod(bar)
def test(self, baaz):
self.tagada['bar'](baaz)
Neat! I like this one.
Not me - with the wrapping so far away from the definition, it's too
easy to miss part of the "process" when you come back to this code 6
month later.
class Foo4(object):
""" working solution 2 : use a lambda """
@staticmethod
def bar(baaz):
print baaz
tagada = {'bar': lambda x : Foo4.bar(x)}
def test(self, baaz):
self.tagada['bar'](baaz)
Huh? How does this one work? After all, while in Foo4 body, the Foo4
does not exist yet? Does lambda defer evaluation to runtime (when it's
executed) or smth?
or smth, yes !-)
A lambda expression evals to an ordinary function - just like a def
statement - so Foo4 is not resolved until Foo4.tagada['bar'] is actually
called.
""" and as a "less worse" solution """
def foo5bar(baaz):
print baaz
class Foo5(object):
tagada = {'bar': foo5bar}
bar = staticmethod(foo5bar)
def test(self, baaz):
self.tagada['bar'](baaz)
Yes. I probably should have stayed with this one in the first place. I
feel bad for using up bandwidth and people's attention with such stuff...
Why so ? You learned something, I learned something, and quite a few
other people will now have a chance to learn something. Sensible use of
bandwith as far as I'm concerned. wrt/ people's attention, don't worry,
it's up to the reader to pay attention or skip the whole topic !-)
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