Consider @_ as being any variable with higher scope than any local my'd variables found within the timethese code.

Now consider the case that I don't want to time 1,000,000 iterations of the exact same case. Rather, I would like time 1,000,000 iterations of my code on various cases.

In fact, for real world benchmarking (rather than simply using a benchmark to profile a particular (simple) peice of code), you would probably want to run your timethese using a statistical sample, or even real sample of test cases.

If timethese could somehow magically (after all how is it going to know which global variables you want to reset? isn't that what my is for anyway?) reset the code to it's initial state (with zero time cost to boot!), then you would not be able to do a simple benchmark such as:

(warning pseudo code) 

srand; timethese(factorial(int rand*1000), 1 000 000);

[download]
Which would give you a sort of average performance of your code over certain input ranges. However you could not do this benchmark if timethese magically reset your initial state (because then you would pick the same random number a million times).

Please pardon if I'm less than coherent, I wanted to make sure I posted something today that was semi-useful, however I didn't get to manage it until the wee hours of the morning.

Ciao,
Gryn

In reply to Magic state resets by gryng
in thread timethese, and pushing array values by husker

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