First of all, i'd write:

print $var ? 'yes' : 'no'
[download]

btw. it's a 'ternary' operator. I cannot agree with your results, my perl (5.6.1 and 5.8.0) lets ?: be only about 13% faster:

use Benchmark qw/cmpthese/;

our @values = (1,0,undef,50,'yes','no','0E0',0e0,0);

my $subs = {

    ifelse => sub {foreach(@values){
        my $x;
        if($_){$x = 'yes'}
        else  {$x = 'no'}
    }},

    trinary => sub {foreach(@values){
        my $x;
        $x = $_ ? 'yes' : 'no'
    }},

};

$_->() for values %$subs;

cmpthese( $ARGV[0] => $subs );
[download]

And to finally (not) answer your question: The ?: operator is much "lighter" than if-else, it is one expression without scope, whereas the if-block can have it's own lexicals. If you wanted to have the functionaltiy of if-else in a ?: construct, you'd have to use do BLOCK, which already slows down the whole thing...

UPDATE: Aristotle is of course right about the "ternary" operator.

btw. it's a 'trinary' operator.

If you correct someone's vocabulary, please do it right. :-) The term is ternary.

Makeshifts last the longest.

Actually, either "Ternary" or "Trinary" is acceptable.

--MrNobo1024
s]]HrLfbfe|EbBibmv]e|s}w}ciZx^RYhL}e^print

I'm sinking into the ground... thanks (must have come from the german "trinär")

--
http://fruiture.de

First of all, i'd write:print $var ? 'yes' : 'no' wouldnt this print yes or no depending on $var...it looks like the Anonymous Monk wants to print yes or no depending on whether $var has a value or not

 $var ? print 'yes' : print 'no'
[download]

seems right to me, am i missing something?

Update: I just started learning how ?: works, so i just wanted to know why

print $var ? 'yes' : 'no'
[download]

will also work, i guess im not understanding how it evaluates $var...the way im reading ?: is if 1st arg (print $var) then second (yes) else third(no) so how does it know that you actually want to print yes or no? with the way im looking at it, it is

if(print $var){
 'yes'
}else{
 'no'
}
[download]

anyone care to explain to me, id appreciate it greatly

Think of it as:

   print ( $boolean ? $true_value : $false_value );
[download]

or in your terms:

   print ( if($var}{ 
             'yes'
           }else{
             'no'
           }
   );
[download]

I like this less because it is pseudo-code that looks
much like code. So it seems to imply many things that
aren't true. The conditional operator is only an
operator not a statement.

Oh, one thing I meant to say earlier, but forgot about: the if statement and the ?: operator aren't really the seperate beasts they appear to be. See the documentation of B::Deparse, and the section on -q, specificly.

perl -MO=Deparse,-p,-x9 -e "if ($/) {print 1} else {print 2}"

($/ ? do { print(1) } : do { print(2) });
-e syntax OK

perl -MO=Deparse,-p,-x9 -e "$/?print 1:print 2"
($/ ? print(1) : print(2));
-e syntax OK
[download]

All the speed diference you see is from those do{}s. Moral of the story? Perl is even stranger then it looks, it has a poor optimizer, do{} is expensive, and other. Pick any combination you feel like.