Somewhat recently, I discovered that when you modify the scalar variable allocated inside of a foreach loop, you can modify the array. While I don't have any trouble finding uses for this, I'm puzzled why it would be used instead of map.

For example, the following operations produce identical output:

@array = qw/1 2 3 4 5/;
foreach $item (@array){
    $item *= 2;
}
print join('-', @array), "\n";

@array = qw/1 2 3 4 5/;
@array = map {$_ *= 2} @array;
print join('-', @array), "\n";

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Is there a reason to choose one operator over the other besides personal preference?

In reply to When would you choose foreach instead of map? by jpfarmer

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