Worst ideas/features in programming languages?

[Timon Gehr]

On 1/6/22 06:58, Paul Backus wrote:
>>
> 
> Perhaps this is a better illustration:
> 
>      struct A {
>          B opArgs() { return B(); }
>      }
> 
>      struct B {}
> 
>      string fun(A) { return "A"; }
>      string fun(B) { return "B"; }
> 
>      void main() {
>          assert(fun(A()) == "A"); // fails
>      }

BTW, it should work like this:

```d
void foo(string x){}       // <- a string, not a tuple

void foo(string x,){}      // <- unary tuple
void foo((string,) t){}    // <- unary tuple

void foo(string x,int y){} // <- 2-tuple
void foo((string,int) t){} // <- 2-tuple
```

So perhaps your example would not even work that way; unary tuples 
shouldn't decay into the underlying type. The concept will need some 
fleshing out. Maybe it's indeed too hard to actually retrofit this into 
the language...