Re: Returning value or key from a hash

use strict;
use warnings;

my %hash = (
  foo => 'bar',
  42  => 23,
  hello => 'world',
);

my @interesting_keys = qw(foo hello);
my @values = map { $hash{$_} } @interesting_keys;

my @interesting_values = qw(bar 23);
my %reversed_hash = reverse %hash;
my @keys = map { $reversed_hash{$_} } @interesting_values;
[download]

Update: Made the code conform to strict, after tirwhan's note.

Comment on Re: Returning value or key from a hash Select or Download Code

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Re^2: Returning value or key from a hash by tirwhan (Abbot) on Apr 07, 2006 at 12:47 UTC
~~You're missing a `my` before the `@values` and `@keys` arrays.~~Update: Not any more. And while I'm nitpicking :-), personally I find it clearer to use a hash slice instead of `map`: `@values = @hash { @interesting_keys }; @keys = @reversed_hash { @interesting_values };` [download] YMMV of course. All dogma is stupid.	[reply] [d/l] [select]
Re^2: Returning value or key from a hash by tlm (Prior) on Apr 07, 2006 at 14:18 UTC
Reversing a hash is cool but dangerous. If the original hash has repeated values, reversing it loses information. the lowliest monk	[reply]
Re^3: Returning value or key from a hash by Corion (Patriarch) on Apr 07, 2006 at 16:39 UTC
But in this case, I assume the hash is reversible, as the original post doesn't mention what to do in conflicts :)	[reply]
Re^4: Returning value or key from a hash by Gavin (Archbishop) on Apr 07, 2006 at 20:07 UTC
It worked for me just fine Cheers all!!	[reply]