Michael,

f> So then I tried creating a stored procedure as an intermediary, which could
f> detect the pattern error and raise an exception. Unfortunately, it appears
f> that SPs can't be used as part of a predicate. Is there a way around this?

the expression (select RESULT from SP_REGEXMATCH(...)) can be used in
a predicate. Until stored functions are implemented in Fb, I think
this is your best bet.

And, I agree that a way to signal an exception from a UDF would be a
very useful addition, although that wouldn't save you from doing
exception trapping in your UDF's body, to convert a language (or
possibly hardware/external) exception to whatever machanism is
implemented in Firebird's UDF API.

Ciao
--
Nando Dessena
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