List comprehension with if-else

[Carl Meyer]

Hi Larry,

On 10/28/2015 10:25 AM, Larry Martell wrote:
> I'm trying to do a list comprehension with an if and that requires an
> else, but in the else case I do not want anything added to the list.
> 
> For example, if I do this:
> 
> white_list = [l.control_hub.serial_number if l.wblist ==
> wblist_enum['WHITE']  else None for l in wblist]
> 
> I end up with None in my list for the else cases. Is there a way I can
> do this so for the else cases nothing is added to the list?

You're not really using the if clause of the list comprehension here,
you're just using a ternary if-else in the result expression. List
comprehension if clauses go at the end, and don't require an else:

    [l.foo for l in wblist if l.bar == "baz"]

Carl

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