In [my code](https://play.nim-lang.org/#ix=25jt), the compiler does not like
the way I return the `solve` closure iterator with generic parameters and
prints the error `'solve' doesn't have a concrete type, due to unspecified
generic parameters.`
I don't understand the reason for such message, as both generic parameters are
instantiated by the call of the enclosing proc.
Also, note that if you remove the second generic parameter of the `solve`
iterator, using the following code, now the program compiles...
...
iterator solve[T]: Solution[T] {.closure.} =
yield solution
try:
return solve[T]
...
Run
Of course, in the original code, I need both `T` and `V` generic parameters in
real `solve`.
