Templates and function parametes

[Rikki Cattermole via Digitalmars-d-learn]

On 9/08/2014 6:19 p.m., Paul D Anderson wrote:
> When I try to compile these two functions, the second function is
> flagged with an already defined error:
>
> bool testRoundTrip(T, U)(T first, U second) if (isIntegral!T &&
> isFloatingPoint!U)
> {
>      return false;
> }
> bool testRoundTrip(U, T)(U first, T second) if (isIntegral!T &&
> isFloatingPoint!U)
> {
>      return false;
> }
>
> They look to me to be distinct functions, one with an integral parameter
> followed by a floating point parameter and the other with a floating
> point parameter followed by an integral parameter.
>
> At first I thought this was a template problem, but the following code
> also raises the same error.
>
> bool testRoundTrip(int first, double second)
> {
>      return false;
> }
> bool testRoundTrip(double first, int second)
> {
>      return false;
> }
>
> What's the problem?

Cannot reproduce on either 2.065 or git head (according to dpaste).

import std.traits;

bool testRoundTrip(T, U)(T first, U second) if (isIntegral!T && 
isFloatingPoint!U)
{
     return first == 1;
}
bool testRoundTrip(U, T)(U first, T second) if (isIntegral!T && 
isFloatingPoint!U)
{
     return second == 2;
}

void main(){
	int x = 1;
	double y = 1.1;
	assert(testRoundTrip(x, y));
	
	x = 2;
	y = 2.2;
	assert(testRoundTrip(y, x));
	
	assert(testRoundTrip(1, 1.1));
	assert(testRoundTrip(2.2, 2));
}