Anonymous Hash Slices - syntax?

Question

I love hash slices and use them frequently:

my %h;
@h{@keys}=@vals;

Works brilliantly! But 2 things have always vexed me.

First, is it possible to combine the 2 lines above into a single line of code? It would be nice to declare the hash and populate it all at once.

Second, is it possible to slice an existing anonymous hash... something like:

my $slice=$anonh->{@fields}

Answer 1

• First question:

  my %h = map { $keys[$_] => $vals[$_] } 0..$#keys;
  

  or

  use List::MoreUtils qw( mesh );
  
  my %h = mesh @keys, @vals;
  

• Second question:

  If it's ...NAME... for a hash, it's ...{ $href }... for a hash ref, so

  my @slice = @hash{@fields};
  

  is

  my @slice = @{ $anonh }{@fields};
  

  The curlies are optional if the reference expression is a variable.

  my @slice = @$anonh{@fields};
  

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