TMCL: RegExes on non-occurrence values

Hi all,

TMCL supports only RegExes on occurrence values. IMO this is a bug.
Why is the following forbidden:

    onto:reference-id isa tmcl:name-type;
      matches-regexp("[0-9]{2}[A-Z]+[0-9]+").

Do we have a good reason to limit RegExes to occ. values? Why
shouldn't they be allowed on name (and variant) values?

Best regards,
Lars
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