Need an identity operator because lambda is too slow

[Gabriel Genellina]

En Sun, 18 Feb 2007 23:31:53 -0300, Sean McIlroy <sean_mcilroy at yahoo.com>  
escribió:

> On Feb 17, 9:59 pm, "Deron Meranda" <deron.mera... at gmail.com> wrote:
> [snip]
>
> this may be really dense, but i'm curious what's wrong with the
> "multiplexer" idiom:
>
> for item in some_sequence:
>         item2 = (not some_rare_condition and item) or \
>                 (some_rare_condition and
> some_transform_function(item))
>         ..... # more stuff

The main concern of the OP was that lambda x:x is slow, so it's better to  
move the condition out of the loop.
Also, this and/or trick does not work when the Boolean value of item is  
false (like 0, (), []...)

-- 
Gabriel Genellina