[Python-Dev] Lambda [was Re: PEP 8 modernisation]

[André Malo]

* Stephen J. Turnbull wrote:

> Chris Angelico writes:
>  > On Thu, Aug 1, 2013 at 5:58 PM, Alexander Shorin <kxepal at gmail.com> 
wrote:
>  > > fun = lambda i: i[1]
>  > > for key, items in groupby(sorted(items, key=fun), key=fun):
>  > >   print(key, ':', list(items))
>  >
>  > I'd do a direct translation to def here:
>  >
>  > def fun(i): return i[1]
>  > for key, items in groupby(sorted(items, key=fun), key=fun):
>  >   print(key, ':', list(items))
>
> As long as it's about readability, why not make it readable?
>
>     def second(pair): return pair[1]
>     for key, items in groupby(sorted(items, key=second), key=second):
>         print(key, ':', list(items))
>
> I realize it's somewhat unfair (for several reasons) to compare that
> to Alexander's "fun = lambda i: i[1]", but I can't help feeling that
> in another sense it is fair.

Seems to run OT somewhat, but "second" is probably a bad name here. If the 
key changes, you have to rename it in several places (or worse, you DON'T 
rename it, and then the readability is gone).
Usually I'm using a name with "key" in it - describing what it's for, not 
how it's done. The minimal distance to its usage is supporting that, too.

nd
-- 
"Das Verhalten von Gates hatte mir bewiesen, dass ich auf ihn und seine
beiden Gefährten nicht zu zählen brauchte" -- Karl May, "Winnetou III"

Im Westen was neues: <http://pub.perlig.de/books.html#apache2>