Hello docdurdee,

The problem with this approach is that SOMEKEY might also appear elsewhere in the hash: as a substring of another key, or as a value. The first case can be tackled by adding word boundaries to the regex: $yaml =~ s{\bSOMEKEY\b}{SomeKey}. But I don’t see any obvious solution to the second case:

#! perl
use strict;
use warnings;
use Data::Dump;
use YAML::XS;

my $hash = { Fred => 'Wilma', Frederick => 'Mary', Barney => 'Fred' };
my $yaml =   Dump $hash;
   $yaml =~  s/\bFred\b/FRED/;
   $hash =   Load $yaml;
dd $hash;
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The output I (happen to?) get:

 0:26 >perl 1186_SoPW.pl
{ Barney => "FRED", Fred => "Wilma", Frederick => "Mary" }

 0:30 >
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Of course, you can add a /g modifier to the substitution, but you’ll still get the value changed as well, when you don’t want it to be. :-(

Update: On second thought, I think this should work for most cases:

$yaml =~ s/(?<=\n)Fred(?=:)/FRED/g;
[download]

Hope that helps,