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From: Victor Porton <porton@narod.ru>
Newsgroups: comp.lang.ada
Subject: Comparing version numbers
Date: Mon, 13 Nov 2017 04:39:11 +0200
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Xref: feeder.eternal-september.org comp.lang.ada:48842
Date: 2017-11-13T04:39:11+02:00
List-Id: <comp.lang.ada>

Not sure if it is quite on-topic, because it is more about general 
programming ideas rather than about Ada. (However, a solution in Python or 
Ruby or JavaScript would more likely used regexps than Ada.)

Suppose I have two version numbers of a software. I need to check which of 
the two is greater.

Lexical order string comparison does not work:

"2.3" vs "11.4".

I could split it by "." and compare the numbers. But a component of a 
version numbers may be nonnumeric like:

"1.2beta".

What to do?

It should work for example for all Debian packages containing interpreters 
(for example, "2.7" for "python" package).

-- 
Victor Porton - http://portonvictor.org