Neat: UFCS for integer dot operator suffix

[Andrei Alexandrescu]

On 9/24/12 9:36 AM, Philippe Sigaud wrote:
> On Mon, Sep 24, 2012 at 2:28 PM, bearophile<bearophileHUGS at lycos.com>  wrote:
>> monarch_dodra:
>>
>>
>>> I tried this, and found it neat that it works:
>
> I used this in a small unit library (partially accessible on github),
> to obtain code like:
>
> auto distance = 100.km;
> auto speed = 130.km/h; // division works, too.
>
> auto timeToDestination = (distance/speed).hour; // distance/speed
> gives seconds =>  transformed in hours.
>
> It was a nice exercise in using UFCS and mixins to create your own
> unit library (not only IS, but ay kind of unit library).
>
> And, you know what? I *never* used it after coding it. These examples
> are cute, they make for nice blog posts for F#, but the real-world
> usage is dubious to me (I know they were space-programs crashes)
>
> I quite like the implicit message in units: use the type system to
> help you catch errors are compile-time. Add to that a nice syntax and
> a showcase for D's generational capabilities and it's quite nice.
>
> But, to my eyes, it's but a toy.

I wouldn't read too much into it. You're a library author, not (I 
assume) a scientific computing guy. So beyond playing with a few 
examples, your work on this library is done - you wouldn't be a client 
of it for the simple reason you don't intensively work with kilometers, 
speeds, dollars, and such. It's possible that a good and usable library 
of units could add value to a category of users.


Andrei