>>>>> "RArul" == RArul <[EMAIL PROTECTED]> writes:
RArul> a) Why do perl gurus exhort, not to use 'grep' or 'map'
RArul> functions under void context?
It is only an artifact of implementation that altering $_ can alter
the input list. The purpose of map or grep is to process a list to
produce an output result, not to alter an input list.
I abused the "$_ is aliased" feature of grep in the Perl3 days, and I
regret that, because it became a part of the culture through my
prolific postings.
Even in a void context, grep and map build up an output list, so it's
wasting CPU to do that.
At first you could argue that there really wasn't anything as concise
as:
grep s/foo/bar/, @list;
but now we have
s/foo/bar/ for @list;
which is even shorter. :)
So for those many reasons, we who have been using Perl for more than
10 years say no to grep/map in void context.
RArul> b) What other functions, are to be avoided in 'void' context?
Well, anything whose primary purpose is to "return" something. Like
"?:", for example. I can't think of many others at the moment, sorry.
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