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

[Samuele Pedroni]

Terry Reedy wrote:
> Some people write
>     somename = lambda args: expression
> instead of the more obvious (to most people) and, dare I say, standard
>     def somename(args): return expression
>
> The difference in the result (the only one I know of) is that the code and 
> function objects get the generic name '<lambda>' instead of the more 
> informative (in repr() output or tracebacks) 'somename'.  I consider this a 
> disadvantage.
>
> In the absence of any compensating advantages (other than the trivial 
> saving of 3 chars), I consider the def form to be the proper Python style 
> to the point I think it should be at least recommended for the stdlib in 
> the Programming Recommendations section of PEP 8.
>
> There are currently uses of named lambdas at least in urllib2.  This to me 
> is a bad example for new Python programmers.
>
> What do our style mavens think?
>   
I found only an example in my personal recent code:

START = "<!-- *db-payload-start* -->"
END = "<!-- *db-payload-end* -->"
TITLEPATTERN = lambda s: "<title>%s</title>" % s

this three are later used in a very few .find() and .replace() 
expressions in the same module. I suppose my point is that while I agree 
it should be discouraged and is really silly to do it for the few chars 
gain, it can be used to some effect in very rare cases.