I'm standardizing some libs for CPAN release and amazed at how much I switched between subs and 'use constant' for class variables

I know people are peculiar to each one, but thats not my question...

I decided to do a quick benchmark between the two and was surpised -- 'use constant' was significantly faster for use as class methods , 1/3 the time of calling a sub.

Does anyone know why? I was under the impression that use constant just creates a sub in the namespace -- so I expected it to have the same performance as using an explicitly defined subrouting. I was kind of shocked to see the difference in execution time.

The speed difference is negligble for most uses -- it took 10k calls to show the difference beyond a margin of error. but at 10 , 1k 10k, 100k and 1MM calls , the difference still is roughly 3x longer for an explicit sub than a 'use constant' defined sub.

In reply to OOP - Constant Vs. Subroutine by 2xlp

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