Just to add something else, here is how map and grep would look if they didn't exist. 
# @out = map { EXPRESSION } @in
my @out;
foreach $_ ( @in ) {
  push @out, EXPRESSION;
}

# @out = grep { CONDITION } @in
my @out;
foreach $_ ( @in ) {
  push @out, $_ if CONDITION;
}

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Using the functions map and grep saves us typing these commonish constructs every time we need them.
Perl function list: <LAZY> map grep </LAZY> for foreach

In reply to Re: Map and Grep by repson
in thread Map and Grep by Anonymous Monk

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