export declare type DiscriminateUnion<T, K extends keyof T, V extends T[K]> = T extends Record<K, V> ? T : never;
export interface EnterExitVisitor<T extends B, B, S, R = void> {
    enter?: (node: T, path: B[], scope: S) => R;
    exit?: (node: T, path: B[], scope: S) => R;
}
interface TaggedInterface<E> {
    type: E;
}
export declare type GenericVisitor<Enum extends string | number, NodeType extends TaggedInterface<Enum>, State, Ret> = {
    [key in Enum]?: EnterExitVisitor<DiscriminateUnion<NodeType, 'type', key>, NodeType, State, Ret>;
};
export declare function enterNode<Enum extends string | number, NodeType extends TaggedInterface<Enum>, State, Ret>(node: NodeType, visitors: GenericVisitor<Enum, NodeType, State, Ret>[], path: NodeType[], scope: State): Ret | undefined;
export declare function exitNode<Enum extends string | number, NodeType extends TaggedInterface<Enum>, State, Ret>(node: NodeType, visitors: GenericVisitor<Enum, NodeType, State, Ret>[], path: NodeType[], scope: State): Ret | undefined;
export {};