Here's another way to do what you want, without creating an intermediate %keepers hash:

use strict;
use warnings;

use Data::Dumper;

# Data Structure
my %h = (
    'a' => 'z',
    'b' => 'y',
    'c' => 'x',
    'd' => 'w',
);

my @to_keep = qw{ a c };

%h = map { $_ => $h{$_} } @to_keep;

print Dumper \%h;

[download]

Update: If by chance your @to_keep array might contain elements that do not necessarily occur as keys in your input hash, it would probably be better to change the penultimate line to:

%h = map { $_ => $h{$_} } grep { defined $h{$_} } @to_keep;

In reply to Re: Hash assignments using map by Not_a_Number
in thread Hash assignments using map by njcodewarrior

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