But you still had to create a huge array in order to benefit from the optimisation; which kinda negates the purpose.

This: perl -E"@a=1..1e9; for( reverse @a ) { print $_; <> }" consumes 18GB (that's Gigabytes!) of memory

Whereas this: perl -E"for( -1e9..1 ) { print -$_; <> }" iterates the same range and consumes only 1.8MB of ram.

Four orders of magnitude more memory, or a minus sign. My choice is simple; how about yours?

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^3: counting backward (optimize foreach reverse low .. high by BrowserUk
in thread counting backward by ag4ve

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