template error instantiating

[Maxim Fomin]

On Saturday, 17 November 2012 at 18:28:10 UTC, ref2401 wrote:
> I get "template instance main.MyClass!(int) error 
> instantiating" in the following case:
>
> public class MyClass(TStuff)
> {
> 	public void foo(TStuff item)
> 	{}
>
> 	public void foo(TRange)(TRange items)
> 	if (isInputRange!TRange && is(ElementType!TRange == TStuff))
> 	{}
> }
>
> void main(string[] argv)
> {
> 	MyClass!int instance = new MyClass!int();
>
> 	return;
> }
>
> but if i rename one of the "foo" overloads then code will be 
> compiled.

Full error message is:

Error: template main.MyClass!(int).MyClass.foo(TRange) if 
(isInputRange!(TRange) && is(ElementType!(TRange) == TStuff)) 
conflicts with function main.MyClass!(int).MyClass.foo at 
main.d(3)
main.d(13): Error: template instance main.MyClass!(int) error 
instantiating

That's why renaming foo makes dmd happy. Alternatively you can 
add extra dummy parenthesis in the first foo to make it template 
function. This is not the first case I see adding parenthesis to 
function declarations solves compilation errors.