Because these 'groups' names ( that I want to use as hash names ) will also come from a external file.

Exactly, they can all go into a hash, you can have 

$hashref->{group1}{dogs}{fido}{breed}='doberman';
$hashref->{group1}{dogs}{fido}{age}=12;
$hashref->{group11}{humans}{larry}{age}= undef;
...

[download]
or anything -- should really read varvarname

In reply to Re^5: variable as hash name by Anonymous Monk
in thread variable as hash name by blackzero

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