/******************************************************************************
 *
 * Tree repair distance.
 *
 * Computes the shortest sequence of edits to transform tree A into tree B.
 *
 * This algorithm is intended to be used to score shopping carts, by reporting
 * the number of edits to convert an observed cart to an expected cart.
 *
 * Edit cost assumptions
 *   1. any subtree can be deleted in its entirety is a single edit.
 *   2. adding a single instance of specific item that is its generic's default
 *      form is a single edit. This applies to top-level products, and their
 *      children.
 *   3. changing an attribute value is a single edit.
 *   4. changing a quantity is a single edit.
 *
 ******************************************************************************/
export interface DiffResults<S> {
    cost: number;
    edits: Array<Edit<S>>;
}
export declare enum EditOp {
    NONE = 0,
    DELETE_A = 1,
    INSERT_A = 2,
    REPAIR_A = 3
}
export interface Edit<STEP> {
    op: EditOp;
    cost: number;
    steps: STEP[];
}
export interface IRepairs<S, T> {
    delete(item: T): Edit<S>;
    insert(item: T): Edit<S>;
    repair(observed: T, expected: T): Edit<S>;
}
export declare type TreeDiffFunction<S, T> = (costs: IRepairs<S, T>, observed: T[], expected: T[]) => DiffResults<S>;
export declare function treeDiff<S, T>(costs: IRepairs<S, T>, observed: T[], expected: T[]): DiffResults<S>;