What's wrong with D's templates?

[Yigal Chripun]

On 19/12/2009 01:31, Lutger wrote:
> Yigal Chripun wrote:
>
>> On 18/12/2009 02:49, Tim Matthews wrote:
>>> In a reddit reply: "The concept of templates in D is exactly the same as
>>> in C++. There are minor technical differences, syntactic differences,
>>> but it is essentially the same thing. I think that's understandable
>>> since Digital Mars had a C++ compiler."
>>>
>>>
> http://www.reddit.com/r/programming/comments/af511/ada_programming_generics/c0hcb04?context=3
>>>
>>>
>>> I have never touched ada but I doubt it is really has that much that
>>> can't be done in D. I thought most (if not all) the problems with C++
>>> were absent in D as this summary of the most common ones points out
>>> http://www.digitalmars.com/d/2.0/templates-revisited.html.
>>>
>>> Your thoughts?
>>
>> I don't know Ada but I do agree with that reddit reply about c++ and D
>> templates. D provides a better implementation of the exact same design,
>> so it does fix many minor issues (implementation bugs). An example of
>> this is the foo<bar<Class>>  construct that doesn't work because of the
>> ">>" operator.
>> However, using the same design obviously doesn't solve any of the deeper
>> design problems and this design has many of those. An example of that is
>> that templates are compiled as part of the client code. This forces a
>> library writer to provide the source code (which might not be acceptable
>> in commercial circumstances) but even more frustrating is the fact that
>> template compilation bugs will also happen at the client.
>
> Well yes, but the .NET design restrict the generic type to a specific named
> interface in order to do type checking. You may find this a good design
> choice, but others find it far more frustrating because this is exactly what
> allows for a bit more flexibility in a statically typed world. So it is not
> exactly a problem but rather a trade-off imho.

The .Net implementation isn't perfect of course and has a few issues 
that should be resolved, one of these is the problem with using 
operators. requiring interfaces by itself isn't the problem though. The 
only drawback in this case is verbosity which isn't really a big deal 
for this.