Ideally, all Perl array indices are of size_t. See perlguts:

SV**    av_fetch(AV*, SSize_t key, I32 lval);

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I'm not sure what you mean by "without using an external lib". Every array element in Perl takes at least 16 bytes, on a 64-bit Perl, 24 bytes.

In reply to Re: internal size of array indices limit? by Corion
in thread internal size of array indices limit? by f77coder

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