[Python-Dev] PEP 8: Discourage named lambdas?

[Greg Ewing]

Raymond Hettinger wrote:

>   lastname_firstname = lambda r: (r[0].lower(), r[5].lower())
>   for k, g in groupby(iterable, key=lastname_firstname): ...
> 
> That transformation adds clarity.  Going further and creating a separate
> def-statement outside the current function would just move the relevant
> code farther away and impair readability.

It doesn't have to be outside the function -- it can be
in exactly the same place as the lambda assignment above.

   def lastname_firstname(r):
     return (r[0].lower(), r[5].lower())
   for k, g in groupby(iterable, key=lastname_firstname):
     ...

Maybe "def is an executable statement" is another thing
people have a blind spot about?

-- 
Greg