Re: version comparison functions

[David Kastrup]

Jason Rumney <address@hidden> writes:

> Kim F. Storm wrote:
>
>>..but now that it has happened, I think it makes sense for these
>>functions to accept an optional argument to limit the number of
>>version string elements to compare.  E.g.
>>
>>       (version= "22.0.50" "22.0.50.37")    => nil
>>       (version= "22.0.50.36" "22.0.50.37") => nil
>>
>>       (version= "22.0.50" "22.0.50.37" 3)    => t
>>       (version= "22.0.50.36" "22.0.50.37" 3) => t
>>  
>>
> This may be useful as an addition to a general version number
> comparison, but for Emacs version numbers, I think we should DTRT
> based on the shorter of the two arguments:
>
> (version= "22" "22.0.50.37") => t

That would mean
(version= "22" "22.0.50.37") => t
(version= "22" "22.1.50.37") => t
(version= "22.0.50.37" "22.0.50.37") => nil

Not exactly endearing to the average mathematician or logician...

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum