block scope?

[Bruno Desthuilliers]

Paul Rubin a écrit :
> aleax at mac.com (Alex Martelli) writes:
> 
>>>>>locals['x']=5
>>
>>Traceback (most recent call last):
>>  File "<stdin>", line 1, in <module>
>>TypeError: 'builtin_function_or_method' object does not support item
>>assignment
> 
> 
> 
> Whoops, yeah, meant "locals()['x'] = 5".
> 
> 
>>I think that ideally there should be a runtime error when assigning an
>>item of locals() with a key that's not a local variable name (possibly
>>excepting functions containing exec, which are kind of screwy anyway).
> 
> 
> I have no opinion of this, locals() has always seemed like a crazy
> part of the language to me and I never use it.  I'd be happy to see it
> gone since it makes compiling a lot easier.

I personally find locals() handy in few cases, like

def output():
   foo = 42
   bar = baaz()
   quux = blah(foo, bar)
   return "the %(bar)s is %(foo)d and the %(quux)s shines" % locals()

or:

class Foo(object):
   @apply
   def bar():
     def fget(self):
        return self._quux / 42
     def fset(self, value):
        self._quux = value * 42
     return property(**locals())


I'd be very unhappy to see it gone...