22 lines
663 B
TypeScript
22 lines
663 B
TypeScript
//// [nominalSubtypeCheckOfTypeParameter.ts]
|
|
interface Tuple<T, S> {
|
|
first: T
|
|
second: S
|
|
}
|
|
|
|
interface Sequence<T> {
|
|
hasNext(): boolean
|
|
pop(): T
|
|
zip<S>(seq: Sequence<S>): Sequence<Tuple<T, S>>
|
|
}
|
|
|
|
// error, despite the fact that the code explicitly says List<T> extends Sequence<T>, the current rules for infinitely expanding type references
|
|
// perform nominal subtyping checks that allow variance for type arguments, but not nominal subtyping for the generic type itself
|
|
interface List<T> extends Sequence<T> {
|
|
getLength(): number
|
|
zip<S>(seq: Sequence<S>): List<Tuple<T, S>>
|
|
}
|
|
|
|
|
|
//// [nominalSubtypeCheckOfTypeParameter.js]
|