You don't have to be especially clever to write something maintainable and cross-platform. If you remove the white-space you can probably use this in Java or POSIX or whatever regex engine you care.

/   A000
|   A1[01][0-9]
|   A12[0-3]
|   A[23][0-9]{2}
|   A4[0-4][0-9]
|   A45[0-9]
|   A999
|   B000
|   B789
|   B79[0-9]
|   B8[0-7][0-9]
|   B88[0-8]
/x

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In reply to Re: Need Set-like Regex for Perl and Java (golf OK) by diotalevi
in thread Need Set-like Regex for Perl and Java (golf OK) by QM

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