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#!/usr/bin/perl
use strict; use warnings;
...
Use of uninitialized value in string comparison (cmp) at ./t7.pl line
+14.
Use of uninitialized value in string comparison (cmp) at ./t7.pl line
+14.
Can't use string ("0") as a subroutine ref while "strict refs" in use
+at ./t7.pl line 6.