I have on occasion had the need to dig down into a complex data structure to change a key (e.g. s/SOMEKEY/SomeKey/, etc. ). The usual digging approach is using loops. Here is a useful trick using a serialized data structure that has saved me some time here and there: 
use YAML::XS;
my $yaml = Dump $hash;
$yaml =~ s/SOMEKEY/SomeKey/;  
$hash = Load $yaml;

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I posted this on Stack Overflow to an old question, but it didn't get many votes. So either it's a bad idea or the question was too old. Anyway, I post it here because I like this trick. Clearly, you should dump the structure and be sure that your replacement won't mess something else up. With power comes responsibility...

In reply to Using serialized data structure to change hash key by docdurdee

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