Wrong. Perl false is !1. (PL_sv_no in the C source) It's a dualvar with a string value of "" and a numerical value of 0.

See: Re^4: m//g behaves strange... (!1). And this snippet:

$ perl -lwe 'for (qw/undef 0 "" !1 1==2/) { print "\n\$a = eval $_;"; 
+$a = eval $_; print "$_:\t|$a|", 1+$a; }'

$a = eval undef;
Use of uninitialized value in concatenation (.) or string at -e line 1
+.
Use of uninitialized value in addition (+) at -e line 1.
undef:  ||1

$a = eval 0;
0:      |0|1

$a = eval "";
Argument "" isn't numeric in addition (+) at -e line 1.
"":     ||1

$a = eval !1;
!1:     ||1

$a = eval 1==2;
1==2:   ||1

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In reply to Re: Logical expression evaluation by benizi
in thread Logical expression evaluation by nghosh

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