Surprisingly, building a list from 1 (or 0 or any integer) using the x op seems to be appreciably (about 25%) faster than using undef?

(1)x10000 is slightly faster 1 .. 10000, 4% or so. Presumably the need for an extra incr operator between stores, though on some architectures that have an auto-increment , the cost of a store would be the same as a incr-and-store.

I can't detect any difference in the memory size. 408k for a list of 100,000 on my machine, which translates to 4 bytes per value plus a little overhead.

Examine what is said, not who speaks.

The 7th Rule of perl club is -- pearl clubs are easily damaged. Use a diamond club instead.

In reply to Re: Re^3: Problem emulating built-ins like map and grep. by BrowserUk
in thread Problem emulating built-ins like map and grep. by BrowserUk

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