Interface Matcher<T, R, Rem>

interface Matcher<T, R, Rem = T> {
    with<const Pat>(
        pattern: Pat,
        then: R | ((v: SelectedArg<Pat, NarrowedBy<Rem, Pat>>) => R),
    ): Matcher<T, R, DeepExclude<Rem, Pat>>;
    with<const Pat>(
        pattern: Pat,
        guard: (v: NarrowedBy<Rem, Pat>) => boolean,
        then: R | ((v: SelectedArg<Pat, NarrowedBy<Rem, Pat>>) => R),
    ): Matcher<T, R, Rem>;
    otherwise(result: R | ((v: Rem) => R)): CompiledFn<T, R>;
    exhaustive(): [Rem] extends [never]
        ? CompiledFn<T, R>
        : ExhaustiveError<Rem>;
    run(value: T): R;
    compile(): CompiledFn<T, R>;
}