Need an identity operator because lambda is too slow

[Steven D'Aprano]

On Sat, 17 Feb 2007 22:19:41 -0800, Raymond Hettinger wrote:

> [Deron Meranda
>>]  I'm looking for something in
>> Python which would act like an identity operator, or I-combinator: a
>> do-nothing function.  The best I know of is:  (lambda x: x), but it is
>> not ideal.
> 
> File a feature request on SourceForge and assign to me.  This has come
> up a couple of times and would be trivial to implement in the operator
> or functools modules.

I'm surprised. The Original Poster specified 

[quote]
What python needs is something like a built-in "operator.identity"
function, which acts like "lambda x:x", but which the byte compiler
could recognize and completely optimize away so there is no function
call overhead.
[end quote]

I would have guessed that optimizing the call away would require support
from the compiler.



-- 
Steven.