Why I hate lambdas (Re: Do any of you recommend Python as afirst programming language?)

[Steven D'Aprano]

On Mon, 24 Mar 2008 06:48:10 -0700, Arnaud Delobelle wrote:

> On Mar 24, 1:26 pm, Steven D'Aprano <st... at REMOVE-THIS-
> cybersource.com.au> wrote:
>> On Mon, 24 Mar 2008 04:33:53 -0400, Terry Reedy wrote:
>> > The fact that .func_name (which is writeable) is not used at first
>> > surprised me until I remembered that code objects can potentially be
>> > used by multiple function objects and hence are not connected to any
>> > one in particular.
>>
>> How does that happen?
> 
> Like this:
> 
>>>> def foomaker(x):
> ...     def foo(y): return x+y
> ...     return foo
> ...
>>>> foo1 = foomaker(1)
>>>> foo2 = foomaker(2)
>>>> foo1.func_code
> <code object foo at 0x73530, file "<stdin>", line 2>
>>>> foo2.func_code
> <code object foo at 0x73530, file "<stdin>", line 2>


Ah, that makes sense. And obvious in hindsight.


> Of course foo1 and foo2 are not the same thing:

Naturally not. They are different functions. The fact that they share a 
small part (func_code) is irrelevant. There's more to a function than the 
code object.



>> And if it is the case, what's the justification for giving them a
>> co_name attribute? Surely the name of the function should be that of
>> the function object, not of one of the shared parts?
> 
>>>> foo1.__name__
> 'foo'
>>>> foo1.func_code.co_name
> 'foo'
> 
> As seen above, func.__name__ and func.func_code.co_name are the same
> thing (until tampered with).

Yes, but what I'm asking is why the code objects have a co_name 
attribute. And even if there's a good reason for code objects to have a 
name, why do tracebacks use func.func_code.co_name instead of 
func.__name__?


-- 
Steven