print "Hey" if $responce eq "hi";
# is optimised/parsed to:
(($responce eq "hi") and print("Hey"));

##</code><code>##

print "Hey" if $responce eq "hi";
(($responce eq "hi") and print("Hey");

##</code><code>##

my @foo = map {int rand 3} 1..1000;

timethese(-15, {
        one => 'for (@foo) { print "$_\n" if $_; }',
        two => 'for (@foo) { if ($_) {print "$_\n";} }',
        three => 'for (@foo) { ($_ and print("\n")); }',
        } );
__END__
Result:
  one: 15 wallclock secs (14.99 usr +  0.01 sys = 15.00 CPU) @ 9421.60/s (n=141324)
  two: 16 wallclock secs (15.01 usr + -0.01 sys = 15.00 CPU) @ 9217.53/s (n=138263)
three: 14 wallclock secs (15.43 usr +  0.01 sys = 15.44 CPU) @ 8842.75/s (n=136532)
another run
  one:  6 wallclock secs ( 7.00 usr +  0.01 sys =  7.01 CPU) @ 9369.33/s (n=65679)
three:  7 wallclock secs ( 7.57 usr +  0.00 sys =  7.57 CPU) @ 9237.78/s (n=69930)
  two:  7 wallclock secs ( 7.44 usr +  0.00 sys =  7.44 CPU) @ 8758.33/s (n=65162)
and another
  two:  9 wallclock secs ( 7.00 usr +  0.00 sys =  7.00 CPU) @ 9757.14/s (n=68300)
  one:  6 wallclock secs ( 7.00 usr +  0.01 sys =  7.01 CPU) @ 9133.24/s (n=64024)
three:  5 wallclock secs ( 7.06 usr +  0.00 sys =  7.06 CPU) @ 8828.47/s (n=62329)