[Development] Adding support for version number comparisons

[Stephen Kelly]

On Sunday, May 11, 2014 13:42:25 Keith Gardner wrote:
> Other comparison rules:
> 
>    1. Numerical groupings should be compared integers instead of characters
>    in order to properly allow for "alpha2" < "alpha11".
>    2. Delimiters should only be used to denote groups of content but be
>    skipped during the compare.  "alpha" == "-alpha" == "~alpha" == ".alpha"
>    1. Can be restricted to the first character if this is too broad.

Given that we're numbering things, your last point would probably be better-
numbered 3 instead of 1 again, right?

Note also that version number schemes for particular software are not constant 
over time.

 https://blog.qt.digia.com/blog/2009/09/03/qt-4th-edition-feature-pack-7/

Are Windows versions in scope?

I changed grantlee versions to drop a 'v' at some point.

 http://www.grantlee.org/downloads/

I'm sure there are other examples in the past and in the future. I didn't read 
closely enough to see if that affects your proposal at all.

My bikeshed color is that a version comparator should only do 'component-wise 
numeric comparison' and shouldn't also try to handle prefixes and suffixes 
etc. I'm just adding that because I don't really support any side of this 
discussion beyond bikeshedding.

Thanks,

-- 
Join us at Qt Developer Days 2014 in Berlin! - https://devdays.kdab.com

Stephen Kelly <stephen.kelly at kdab.com> | Software Engineer
KDAB (Deutschland) GmbH & Co.KG, a KDAB Group Company
www.kdab.com || Germany +49-30-521325470 || Sweden (HQ) +46-563-540090
KDAB - Qt Experts - Platform-Independent Software Solutions