Because you can concatenate a million 32-bit numbers into a single, (4 MB) SV, and avoid having to allocate the other 999,999 SVs which would require 12 MB minimum, and over 220 MB if they were all blessed references and you put them into an array. And much more if you put them into a hash for fast lookup.

A packed string of equal sized elements has all the properties of an array. Very fast indexing and the ability to be spliced. And it uses a huge amount less memory.

Examine what is said, not who speaks.
Silence betokens consent.
Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco.

In reply to Re^10: Techniques On Saving Memory by BrowserUk
in thread Techniques On Saving Memory by Limbic~Region

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