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=== tests/cases/compiler/inferTypeParameterConstraints.ts ===
// Repro from #42636
type SubGuard<A, X extends [A]> = X;
>SubGuard : X
type IsSub<M extends any[], S extends any[]> = M extends [...SubGuard<M[number], infer B>, ...S, ...any[]] ? B : never;
>IsSub : IsSub<M, S>
type E0 = IsSub<[1, 2, 3, 4], [2, 3, 4]>; // [1 | 2 | 3 | 4]
>E0 : [1 | 4 | 2 | 3]
type E1 = [1, 2, 3, 4] extends [...infer B, 2, 3, 4, ...any[]] ? B : never; // unknown[]
>E1 : unknown[]
// Repro from #42636
type Constrain<T extends C, C> = unknown;
>Constrain : unknown
type Foo<A> = A extends Constrain<infer X, A> ? X : never;
>Foo : Foo<A>
type T0 = Foo<string>; // string
>T0 : string
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