[phobos] Ranges using runtime interfaces

[David Simcha]

Wow, you're right.  You can implement a tuple of interfaces.  When I 
wrote the last email saying you couldn't it was late at night in my time 
zone.  I didn't bother double-checking because I had never seen such a 
thing documented or done before.  I got your requested feature of 
implementing multiple output types working at the small cost of having 
to use a string mixin to write the put methods, since static foreach 
never made the cut.  The latest revision is at 
http://pastebin.com/azM0Xnqh .

On 8/21/2010 12:06 AM, Shin Fujishiro wrote:
> David Simcha<dsimcha at gmail.com>  wrote:
>    
>> Hmm.  It's worth considering, but I see at least two problems.
>>
>> 1.  Do we have a practical use case for it?  I don't generally believe
>> in adding complexity without clear use cases for said complexity.
>>      
> I'm not sure.  I/O-related ranges tend to have chunk-writing overloads:
>
>    void put(E value);
>    void put(E[] chunk);
>
> And the Appender has a similar overload for bulk appending.  But such
> ranges can work with only one of those overloads.
>
>
>    
>> 2.  The base interface is OutputRange!(E).  If I change the base
>> interface to OutputRange!(E...), then OutputRange!(uint, double) won't
>> be a subtype of OutputRange!(uint).  This is self-evidently ridiculous.
>> I could maybe make OutputRangeObject!(E...) inherit from
>> OutputRange!(E[0]), OutputRange!(E[1]), ..., OutputRange!(E[$ - 1]), but
>> other than nasty string mixins D doesn't provide a way to inherit from a
>> tuple of interfaces.
>>      
> Oh, really?  That's bad.  I thought tuples could be used in the class
> inheritance list.  IIRC something like the following also does not work
> due to a deep inheritance bug:
>
> interface OutputRange(E...) : OutputRange!(E[1 .. $]) {
>      void put(E[0] e);
> }
>
> Then, maybe we should put off supporting this anyway...
>
>
>    
>> On 8/20/2010 9:26 PM, Shin Fujishiro wrote:
>>      
>>> David Simcha<dsimcha at gmail.com>   wrote:
>>>
>>>        
>>>> In addition to the changes I made last night, I've also made the
>>>> following changes:
>>>>
>>>> 1.  Change name to inputRangeObject/InputRangeObject.
>>>> 2.  Add support for output ranges as outputRangeObject/OutputRangeObject.
>>>> 3.  Remove the now ridiculous looking Hungarian notation on the interfaces.
>>>>
>>>> http://pastebin.com/U83YNJfJ is where it's at.
>>>>
>>>> Any more comments from anyone, or does this look ready to be checked in?
>>>>
>>>>          
>>> Could you make OutputRangeObject able to accept multiple element types?
>>>
>>> template outputRangeObject(E...) {
>>>       auto outputRangeObject(R)(R range) { ... }
>>> }
>>>        
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