[Tutor] Re: Are you allowed to shoot camels? [kinda OT]

[Roel Schroeven]

Chad Crabtree wrote:
> How about a concrete example where lambda is more elegant than a
> named 
> block of code
> 
> aList=['a','bb','ccc','dddd','ee']
> bList=aList[:] #deep copy
> assert not bList is aList
> 
> def sortByLength(item1,item2):
>     return cmp(len(item1),len(item2))
> 
> bList.sort(sortByLength)
> assert bList==['a', 'bb', 'ee', 'ccc', 'dddd']
> 
> aList.sort(lambda x,y:cmp(len(x),len(y)))
> assert aList==['a', 'bb', 'ee', 'ccc', 'dddd']
> 

> Now this is a concrete example of how lambda simplifies code, at 
> least for me because it does not clutter my mental name space. Also
> it is much shorter. However it should be said that this is very much
> a question  of taste.

Indeed. In this case, I like the version without lambda. Naming the 
function serves as documentation, so I don't even need to read an 
interpret the body of the function to know what it does. Assuming that 
the name correctly describes the behavior of course, but I need to check 
that only once. From then on, sort(sortByLength) instantly explains what 
it does, while sort(lambda x,y: cmp(len(x),len(y)) needs much more parsing.

But I agree that there are cases where lambda is more useful and/or clearer.

-- 
"Codito ergo sum"
Roel Schroeven