src/cmd/api/testdata/src/pkg/p4/golden.txt

pkg p4, func NewPair[T1 interface{ M }, T2 interface{ ~int }](T1, T2) Pair
pkg p4, method (Pair[_, X2]) Second() X2
pkg p4, method (Pair[X1, _]) First() X1
pkg p4, type Pair[T1 interface{ M }, T2 interface{ ~int }] struct