Re: grep for hash?

[poolpi]

Just with map:

use strict;
use warnings;
use Data::Dumper;

my $orig = { 'foo' => 2, 'bar' => 4, 'boo' => 1, 'zar' => 5 };
my $dest;

map { /oo/ and $dest->{$_} = $orig->{$_} } keys %$orig;

print Dumper $dest;

__END__
Output:
$VAR1 = {
          'boo' => 1,
          'foo' => 2
        };

hth,
PooLpi

[Fletch]

Map in void context? Bleh. (See map versus for)

[Anonymous Monk]

Should be :D  /oo/ and $dest->{$_} = $orig->{$_} for keys %$orig;

[ikegami]

Written like it's said, "Copy each selected key":

$dest->{$_} = $orig->{$_} for grep /oo/, keys %$orig;

There's no need to twist one's mind to process the parent's expression.