Re: while(<>) { ... } considered harmful

I probably wrong but I'd say map is considered harmful.
I use while(<>){...} all the time but never use map.
Would I run into this problem if I avoid using
map? I guess I just don't understand map.
Why use map?
Comment on Re: while(<>) { ... } considered harmful

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Re^2: while(<>) { ... } considered harmful by Aristotle (Chancellor) on Sep 08, 2002 at 05:15 UTC
Because something like `my @idx = map /(id\d+)/, @items;` is a lot more natural than `my @idx; /(id\d+)/ && push @idx, $1 for @items;` [download] (which is already pushing legibility). Basically when you build one list out of another, non-destructively, `map` is the ticket. It can be in other cases as well, but those can often go either way. Makeshifts last the longest.	[reply] [d/l] [select]
Re: Re: while(<>) { ... } considered harmful by IlyaM (Parson) on Sep 09, 2002 at 09:42 UTC
I disagree with saying that map is considered harmful. As I noted in other reply in this thread its behaviour is consistent with other Perl operators: for/foreach and grep. In my opinion it is `while(<>)`'s magic is wrong. It should localize $_ so it doesn't affect outer scope. -- Ilya Martynov (http://martynov.org/)	[reply] [d/l]