Adding Unicode operators to D

[Simen Kjaeraas]

On Sun, 26 Oct 2008 22:28:16 +0100, Bill Baxter <wbaxter at gmail.com> wrote:

> On Sun, Oct 26, 2008 at 11:02 PM, Simen Kjaeraas  
> <simen.kjaras at gmail.com> wrote:
>> On Sat, 25 Oct 2008 12:14:47 +0200, Spacen Jasset  
>> <spacenjasset at yahoo.co.uk>
>> wrote:
>>
>>> Why unicode anyway? In the same way that editor support is required to
>>> actually type them in, why not let the editor render them. So instead  
>>> of
>>> symbol 'x' in the source code, say:
>>>
>>> m3 = m1 cross_product m2
>>>
>>> as an infix notatation in a similar way to the (uniary) sizeof  
>>> operator.
>>>
>>>
>>> While cross_product is a bit long and unwieldy any editor capable can
>>> replace the rendition of that keyword with a symbol for it. But in  
>>> editors
>>> that don't it means that it still can be typed in and/or displayed  
>>> easily.
>>>
>>> Another option includes providing cross_product as an 'alias' and 'X'
>>> aswell.
>>>
>>> Which then leads on to the introduction of a facility to add arbitary
>>> operators, which could be interesting becuase you can supply any  
>>> operator
>>> you see fit for the domains that you use that require it. -- This  
>>> provide
>>> exactly the right solution though as all the additions would be 'non
>>> standard' and I can see books in the future recommending people not use
>>> unicode operators, becuase editors don't have support for them.
>>
>> This made me think. What if we /could/ define arbitrary infix operators  
>> in
>> D? I'm thinking something along the lines of:
>>
>>
>> operator cross_product(T, U)
>> {
>>  static if (T.opCross)
>>  {
>>    T.opCross(T)
>>  }
>>  else static if (U.opCross)
>>  {
>>    U.opCross_r(T);
>>  }
>>  else
>>  {
>>    static assert(false, "Operator not applicable to operands.");
>>  }
>> }
>>
>> alias cross_product ×;
>>
>>
>> I'm not sure if this is possible, but it sure would please downs. :P
>
> What's the precedence of your user-defined in-fix operator?
>
> --bb

Yup, I realized this myself as well. Seemed like such a great idea when I  
only thought of it for three seconds. :p

-- 
Simen