You're right. it wouldn't work for files greater than memory.

I thought it might for a while because of the in-place sort optimisation that came in somewhere in 5.8.x, that means that:

@ar = sort @r;

[download]

gets converted to sort \@ar; and sorts in place rather then copies the array to the stack and back.

But looking at the code, it doesn't work for tied arrays:

    /* optimiser converts "@a = sort @a" to "sort \@a";
     * in case of tied @a, pessimise: push (@a) onto stack, then assig
+n
     * result back to @a at the end of this function */

[download]
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.
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The start of some sanity?

In reply to Re^3: Sort command equivalent in perl by BrowserUk
in thread Sort command equivalent in perl by sandeepau

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