Tie::Hash::Regex provides that interface you want, but internally loops over all the keys. That's inevitable if you use a regex. If your concern is efficiency, Tie::Hash::Regex is not going to help.

If I correctly understand what you are trying to do, you could actually store your data in a format that's more useful to you, eliminating the need for regexs entirely. 

$hash{$serial}{''} = ...;
$hash{$serial}{O}  = ...;
$hash{$serial}{R}  = ...;

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In reply to Re: regex of hash key on the fly by ikegami
in thread regex of hash key on the fly by martzpet

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