Evaluating two undef values for string equality yields a true result. undef is temporarily promoted to "" (the empty string) in string context. If warnings are enabled, warnings are emitted. 

c:\@Work\Perl\monks>perl -le
"use strict;
 use warnings;
 ;;
 use Data::Dump qw(dd);
 ;;
 my ($value, $alice, $bob);
 ;;
 $value = $alice eq $bob;
 dd 'result of comparison of undefined values', $value;
"
Use of uninitialized value in string eq at -e line 1.
Use of uninitialized value in string eq at -e line 1.
("result of comparison of undefined values", 1)

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Give a man a fish:  <%-{-{-{-<

In reply to Re^5: Learning Programming, desperately need to know what information is contained in scalar variables by AnomalousMonk
in thread Learning Programming, desperately need to know what information is contained in scalar variables by Anonymous Monk

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