opCmp, [partial/total/pre]orders, custom floating point types etc.

[John Colvin via Digitalmars-d]

On Wednesday, 13 January 2016 at 01:43:21 UTC, John Colvin wrote:
> On Wednesday, 13 January 2016 at 01:39:26 UTC, John Colvin 
> wrote:
>> On Wednesday, 13 January 2016 at 00:31:48 UTC, Andrei 
>> Alexandrescu wrote:
>>> [...]
>>
>> I would completely agree, except that we have builtin types 
>> that don't obey this rule. I'd be all in favour of sticking 
>> with total orders, but it does make it hard (impossible?) to 
>> make a proper drop-in replacement for the builtin floating 
>> point numbers (including wrappers, e.g. std.typecons.Typedef 
>> can't handle nans correctly) or to properly handle comparisons 
>> between custom types and builtin floating points (as mentioned 
>> by tsbockman).
>>
>> I am all for keeping it simple here, but I still think there's 
>> a problem.
>
> https://issues.dlang.org/show_bug.cgi?id=15561

https://github.com/D-Programming-Language/phobos/pull/3927