It looks like the OP doesn't need to keep track of the individual file names, so although a hash of hashes seems like a natural thing to do, I think a hash of arrays is all that was requested. (And it looks like sch's reply is meant for Perl6 -- those of us still using Perl5 would say $filedate{...}).

Anyway, here's an approach that does what the OP proposed: 

push( @{$modtimes{substr($filename,0,2)}, $modtime );

[download]
Then it's easy to get the arrays back, one type at a time: 
foreach $type ( sort keys %modtimes ) {
   @times = @{$modtimes{$type}};
   # do something with this set of @times...
}

[download]

In reply to Re: dynamically named arrays by graff
in thread dynamically named arrays by Anonymous Monk

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