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//// [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]
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