map should not be used in a void context, that's why foreach is there.

map { print "$_\n" } (@array);
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foreach (@array) {
   print "$_\n"
}
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These are functionally the same, but map generates a return value that can be assigned to another array, and foreach does not, therefore map is not appropriate. Instead it should be used for its return value:

@squares = map { $_ * $_ } (@array);
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The above code with foreach would have to be:

foreach (@array) {
   push @squares, $_ * $_
}
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When the map function is used as you suggest above, it is being called in void context, which I agree is not as good as for. Having said that, I would suggest that a more perlish idiom of saying the above would not require calling map in void context at all:

print map "$_\n", @array;
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And better still:

print join "\n", @array;
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Just some thoughts.

map should not be used in a void context, that's why foreach is there.

And why then is map allowed to be called in void context? =)

-Waswas

It is addressed in the Perl FAQ.

There are a lot of things you can do with Perl that you shouldn't do.

These are functionally the same, but map generates a return value that can be assigned to another array, and foreach does not, therefore map is not appropriate.

There are also situations where forech aren't appropriate. Like:



foreach(@array){
 push(@tmp, $_) if(/$regex/);
}
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But I respect this way of coding 'cause TMOWTDI.
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kral
(sorry for my english)