Compound Assignment Operators ( +=, *=, etc...)
amk at mira.erols.com
Sun Aug 15 16:52:21 CEST 1999
On Sun, 15 Aug 1999 03:09:14 -0500, Andrew McDowell <drew at getaway.net> wrote:
>Why would you confuse x += y (which would seem to imply the former) to mean
>x.extend(y) ? It _is_ an assignment statement after all..
If you have:
aList = 
bList = aList
aList += [1,2,3]
Do aList and bList still point to the same list? I think people could
argue for either interpretation as being the most intuitive.
Another thing: if the meaning is taken as "x = x + y", this means that
x+=y is really quite inefficient, which will be confusing to people
who've been indoctrinated to believe that '++' lets the compiler
produce better code. That may be true for C, but if you coded "for i
in biglist: resultlist += thingy", you'd do a lot of unnecessary list
A.M. Kuchling http://starship.python.net/crew/amk/
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