I have a hash with the keys being the names and versions of available applications: 
%apps = (
  gcc-3.3 => 1,
  gcc-3.3.1 => 1,
  gcc-3.3.2 => 1,
  gzip-1.2.4a => 1,
  make-3.79.1 => 1,
);

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Given an application name, I need to find the latest available version. For example, given the hash above, if I have "gcc", I want to return "gcc-3.3.2", "make" should return "make-3.79.1", and "cobol" should return false or undef.

I can do this by sorting the keys in reverse order and looking for the first match for, for example /^gcc-/, but that seems... inefficient.

I know I will need to get get more creative in my sorting (for example, when gcc-10.0 is released), but for now let's assume that cmp gives a correct comparision between versions.

Any ideas?



tektsu
kiku wa ittoki no haji kikanu wa matsudai no haji

In reply to Finding the latest available version of a program by tektsu

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