ProtoObject and comparison for equality and ordering

[Mike Franklin]

On Wednesday, 15 May 2019 at 00:08:10 UTC, Andrei Alexandrescu 
wrote:

> This won't work because the result of opCmp is compared against 
> zero. Using a floating point number is likely to be more 
> efficient.

Please consider the fact that some microcontrollers don't have an 
FPU.  Some may have a software floating point implementation but 
consider the cost in flash memory consumption and performance 
implementing such a thing in software.  It seems excessive.

Although it would be much more work, perhaps what is needed is a 
new type (e.g. `struct CmpResult`) with 4 immutable instances 
representing each result and an `opCmp` and `opEquals` 
implementation that does the right thing comparing against 0 or 
whatever else is needed.  Yes, it's more complicated, but I think 
it would scale better.

Mike