man Tie::Array::Sorted () - An array which is kept sorted
NAME
Tie::Array::Sorted - An array which is kept sorted
SYNOPSIS
use Tie::Array::Sorted;
tie @a, "Tie::Array::Sorted", sub { $_[0] <=> $_[1] };
push @a, 10, 4, 7, 3, 4;
print "@a"; # "3 4 4 7 10"
DESCRIPTION
This presents an ordinary array, but is kept sorted. All pushes and unshifts cause the elements in question to be inserted in the appropriate location to maintain order.
Direct stores (CW$a[10] = "wibble") effectively splice out the original value and insert the new element. It's not clear why you'd want to use direct stores like that, but this module does the right thing if you do.
If you don't like the ordinary lexical comparator, you can provide your own; it should compare the two elements it is given. For instance, a numeric comparator would look like this:
tie @a, "Tie::Array::Sorted", sub { $_[0] <=> $_[1] }
Whereas to compare a list of files by their sizes, you'd so something like:
tie @a, "Tie::Array::Sorted", sub { -s $_[0] <=> -s $_[1] }
LAZY SORTING
You may find, after profiling your code, that you do far more stores than fetches. In this case, doing a sorted insertion is inefficient, and you only need to sort on retrieval. You can turn on lazy sorting by tying to the CWTie::Array::Sorted::Lazy subclass, which does the right thing. Naturally, it only re-sorts if data has been added since the last sort.
tie @a, "Tie::Array::Sorted::Lazy", sub { -s $_[0] <=> -s $_[1] };
AUTHOR
Simon Cozens, <simon@cpan.org>
COPYRIGHT AND LICENSE
Copyright 2003 by Kasei, 2004 by Simon Cozens
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.