Check well-kindedness of type application (assumes arities are already checked) -- @M
Check well-kindedness of type application (assumes arities are already checked) -- @M
This check is also performed when abstract type members become concrete (aka a "type alias") -- then tparams.length==1 (checked one type member at a time -- in that case, prefix is the name of the type alias)
Type application is just like value application: it's "contravariant" in the sense that the type parameters of the supplied type arguments must conform to the type parameters of the required type parameters:
e.g. class Iterable[t, m[+x <: t]] --> the application Iterable[Int, List] is okay, since List's type parameter is also covariant and its bounds are weaker than <: Int