Multi expression

[RomainTiennot]

Hello,
I have a trigger that alerts me when he does not have the values (Ready to print), (Print User-Action), Printing ...) and me up an alert for any other.
The following expression works:
(({Xerox 7232: prtError.1.1.iregexp (Ready to print)} | {Xerox 7232: prtError.1.1.iregexp (Print User-Action)} | {Xerox 7232: prtError.1.1.iregexp (Printing. ..) }) # 1 | {Xerox 7232: prtError.1.1.strlen (0)}) # 0

The problem is that sometimes the SNMP back an empty value ("") and I can not seem to put an expresion that works.

Here are my tests:
(({Xerox 7232: prtError.1.1.iregexp (Ready to print)} | {Xerox 7232: prtError.1.1.iregexp (Print User-Action)} | {Xerox 7232: prtError.1.1.iregexp (Printing. ..) }) # 1 | {Xerox 7232: prtError.1.1.strlen (0)}) # 0

(({Xerox 7232: prtError.1.1.iregexp (Ready to print)} | {Xerox 7232: prtError.1.1.iregexp (Print User-Action)} | {Xerox 7232: prtError.1.1.iregexp (Printing. ..) } | {Xerox 7232: prtError.1.1.iregexp ()}) # 1

But none works.
Do you have an idea?

Romain