Big-time newbie, so please don't laugh too hard...

In what order is a compound IF evaluated - right-to-left or left-to-right?

Does Perl immediately stop evaluating a compound IF once a false evaluation occurs?

I am building an IF statement of at least 10 comparisons and want it to evaluate as fast as possible.

A similar example: 

if (($A ne "ONE") && ($B eq "TWO"))
   {
   ...
   }
else
   {
   ...
   }

[download]

So, if the odds are that ($A ne "ONE") will fail more often, should I write:

if (($A ne "ONE") && ($B eq "TWO"))

[download]

-or- should I write:

if (($B eq "TWO") && ($A ne "ONE"))

[download]

Does it matter - does Perl care???

thanks...
-mike

In reply to In what order is a compound IF evaluated? by Anonymous Monk

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