Perl variables will grow as needed. Sometimes it is useful to size an array or hash to accommodate a large number of values, to prevent Perl from repeatedly having to allocate additional space. 

# presize a hash:
keys(%hash) = 10_000;

# size an array:
my @array;
$#array = 10_000;

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Sizing an array to be shorter than it currently is will truncate the array.


TGI says moo

In reply to Re: memory for array by TGI
in thread memory for array by vit

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