return 0 if $uri->path =~ /\?(C=N;O=D|C=M;O=A)?$/;

Update: There are two issues on the that regexp line. On my reply I considered only one. You said you wanted to have 0 returned in case of a match, but you are returning nothing. What you will have is an undefined value.

The second is addressed in the replies below.

In reply to Re: Difficult? regex by olus
in thread Difficult? regex by Anonymous Monk

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