Are you sure about that?

Yes. I am very sure.

Unlike C, perl can do sparse arrays without using lots of memory for the empty slots,

No. It cannot.

The second assignment in your example (on a 64-bit system) results is the allocation of 134 megabytes of ram:

$a[0]=1; print total_size( \@a );;
232

$a[1]=1; print total_size( \@a );;
256

$a[2]=1; print total_size( \@a );;
280

$a[10_000_000]=1; print total_size( \@a );;
134217984

[download]

To gain a better appreciation for how Perl uses memory, see PerlGuts Illustrated and scan down to the AV heading.

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: Array or Hash by BrowserUk
in thread Array or Hash by palanisamy

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