Does anyone know an elegant way to write this?

Perhaps? 

my %small_hash;
my @retain = grep{
    defined $config{ $_ } && $config{ $_ } ## not false
} @interesting_keys;

@small_hash{ @retain } = @config{ @retain };
    
return \%small_hash;

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In reply to Re: Taking a subset of a hash by BrowserUk
in thread [Answered!] Taking a subset of a hash by Narveson

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