Is there any way to differentiate between a type and an alias?

[Steven Schveighoffer via Digitalmars-d-learn]

On Sun, 25 May 2014 18:13:17 -0400, Rene Zwanenburg  
<renezwanenburg at gmail.com> wrote:

> On Sunday, 25 May 2014 at 14:40:06 UTC, Steven Schveighoffer wrote:
>> On Sun, 25 May 2014 04:04:09 -0700, Rene Zwanenburg  
>> <renezwanenburg at gmail.com> wrote:
>>
>>> Given
>>>
>>> alias GLenum = uint;
>>> void glSomeFunction(GLenum, uint);
>>>
>>> Now, is there some way to differentiate between GLenum and uint when  
>>> using ParameterTypeTuple!glSomeFunction?
>>>
>>> I'm writing a function which shows the arguments a GL function was  
>>> called with when an error occurs. The GLenum needs to be printed as a  
>>> stringified version of the constant's name, while the uint is just an  
>>> uint.
>>
>> An alias is simply another name for the same thing. There is no type  
>> difference.
>>
>> You may be able to do some template trickery with template aliases to  
>> detect when an alias is used. But I'd recommend using enum instead of  
>> alias:
>>
>> enum GLenum : uint { constant = value}
>>
>> This creates a genuine new type, and also gives you a place to put  
>> constants. However, it's not implicitly castable from uint, so it has  
>> some drawbacks. You can cast back to uint implicitly though.
>>
>> There is also a library typedef mechanism (in std.typecons perhaps?),  
>> you can look into that. It should have the same limitations as enum.
>>
>
> I'm using Derelict as OpenGL binding, so I can't change the API.Derelict  
> has chosen not to use enum so any C code sample can be used as-is.

I get it. I don't necessarily agree with that, but it's not my library :)

I think it would be difficult to achieve without changing the actual  
function definition. Perhaps you could wrap the functions with your own,  
and use your own enum type. The enum as I defined it above, should  
implicitly cast to uint.

-Steve