regex from plperl

Hi,

I've written following function:

create or replace function dewey(text)
   returns text
   as '
 $_=shift;
 if (/(\d\d\d)/) {
    return "$1";
 } else {
    return("this is not a valid dewey!");
 }' language plperlu;

Then:

libri=# select dewey('432');
           dewey
----------------------------
 this is not a valid dewey!
(1 row)


It seems that regex doesn't work at all.

But regex are quite important for me.
Is There something that I've forgotten?


Best wishes,              \fer
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