Short-circuiting doesn't mean it never evaluates the right operand; short-circuiting means it only evaluates as much as possible to determine the answer. It will still always give the right answer. The truth table for AND is: 

false && false => false   \ Short circuit possible
false && true  => false   /
true  && false => false
true  && true  => true

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If the LHS is false, it will never evaluate the RHS because of short-circuiting. If the LHS is true, it must evaluate the RHS.

But more importantly, the answer you expect is wrong. True and false shouldn't give true.

Here's a demonstration of short-circuiting in effect. 

sub zero  { print "zero\n";  0 }
sub two   { print "two\n";   2 }
sub three { print "three\n"; 3 }

my $x = zero  && two;    print "\$x is = $x\n\n";
my $y = three && zero;   print "\$y is = $y\n\n";
my $z = two   && three;  print "\$z is = $z\n\n";

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zero
$x is = 0     <--- two never called

three
zero
$y is = 0

two
three
$z is = 3

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In reply to Re: Kindly let me know what exactly && does in Perl by ikegami
in thread Kindly let me know what exactly && does in Perl by pritesh

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