Re: Why does this work?

[VonGrass via Digitalmars-d-learn]

On Monday, 23 June 2014 at 08:30:44 UTC, h_zet wrote:
import std.typecons;
auto foo2(R)(R foopara){
    return tuple(foopara, is(R==int));
}

void main(){
    auto tuple(a,b) = foo2(1);
}


I'm expecting some error such as can not act as left value but 
when I compiled this, no error occured. DMD version is DMD64 
v2.065.(ldc2 exited with error function declaration without 
return type)

Why does this work? Or it is a bug?

Looks grammaticallyu correct: R type is guessed/infered from the 
parameter