Parser lookahead...
They even say that it is possible, but it makes producing useful error messages harder and makes the parser more complicated. they are not saying it is not possible, they are just saying it's not preferred to do.
They even say that it is possible, but it makes producing useful error messages harder and makes the parser more complicated. they are not saying it is not possible, they are just saying it's not preferred to do.
a, b := w<type x,y>(z)