in reply to [Answered!] Taking a subset of a hash

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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Re^2: Taking a subset of a hash
by Narveson (Chaplain) on Oct 30, 2010 at 13:28 UTC

    Sorry if I forgot to mention that $config was a reference.

    Doesn't defined $config{ $_ } && $config{ $_ } have the same truth value as $config{ $_ }?

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[select]
      Doesn't defined $config{ $_ } && $config{ $_ } have the same truth value as $config{ $_ }?

      Yes. I was attempting to capture your stated requirements:

      but omits them if their configured value is false, undefined, or nonexistent.

      and got it wrong. It should be:

      exists $config{ $_ } && $config{ $_ }

      [download]
      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]
[d/l]

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