Ambiguous template parameter names

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On Wednesday, 2 May 2018 at 20:32:43 UTC, jmh530 wrote:
> In the function below, there is a template parameter and a 
> normal parameter both with the same name. However, the function 
> returns the normal parameter. The template parameter is 
> effectively ignored. I was surprised by this behavior.
>
> Is this a bug or intentional? I did not see it documented 
> anywhere.
>
>
> ```
> int foo(int val)(int val)
> {
> 	return val;
> }
>
> void main()
> {
>     assert(foo!1(2) == 2);
> }
> ```

It's not a big per se. It's a consequence of the declaration 
expanding to the real template function form (I can't type it all 
out as I'm on my phone), thus the inner `val` from the function 
shadows the one from the template.