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[REBOL] Re: order of evaluating expressions..

From: rotenca:telvia:it at: 24-Dec-2004 13:34

Peter WA Wood wrote:
>Is it really a significant slow down? >
Yes. I often read this question about Rebol, my answer is always Yes. Rebol is slow by itself, if you slow it with an avoidable programming style, you are not doing the right thing. There are many of this cases in Rebol, the combinations of them can lead to a slow program. Often i see program which can become 30-50% faster only using the right syntax. This is a 50-60% gain example with the combination of 4 "Is it really a significant slow down?" cases: 0:00:00.375 [out: copy [] insert tail out to string! 4 * 5 + 3 * 6] 0:00:00.578 [append out: copy [] to-string ((4 * 5) + 3) * 6] Sometime this difference is negligible, sometime is the difference between an usable and an unusable program. And what is negligible today, will be not negligible tomorrow, when you'll add other features and functions to your program. There is an important difference between the syntax of compiled language and interpreted one: in the first case, the compiler can do many optimizations at compile time and you can write code in a more relaxed way; in the second case, all you write will be read and executed "as is" at run time. The programmer is also the optimizer. -- Ciao Romano Paolo Tenca