@macfja/svelte-undoable/types/index.d.ts

Memento design pattern in Svelte

import { Writable } from "svelte/store";
/**
 * Undoable store.
 */
export interface UndoableStore<T> extends Writable<T> {
    /**
     * Change the value to the previous saved state
     */
    undo(): void;
    /**
     * Change the value to the next saved state
     */
    redo(): void;
    /**
     * Indicate if the store value can be revert to a previous state
     */
    canUndo(): boolean;
    /**
     * Indicate if the store value can be change to a next state
     */
    canRedo(): boolean;
    /**
     * Revert the value of the store to the oldest state.
     * If the parameter is `true`, then the store state history is cleared
     * @param {boolean?} clear If `true` the history is cleared
     */
    reset(clear?: boolean): void;
    length(): number;
}
/**
 * Create a store with undo/redo feature
 * @param {*} initial The initial value of the store
 * @param {number?} capacity The maximum number of entry to remember (any number lower than 2 is considered as infinite size)
 * @param {function(*: newValue): boolean} accept The validation function to accept a value to be save in memory.<br/>
 *                                                  Take the new store value as parameter, should return a boolean (`true` to save the value, `false` to dismiss it).<br/>
 *                                                  If ignore, it will accept all value
 * @return {UndoableStore<*>}
 */
export declare function undoable<T>(initial: T, capacity?: number, accept?: (newValue: T) => boolean): UndoableStore<T>;
/**
 * Change the value to the previous saved state
 * @param {UndoableStore<*>} undoableStore The store to use
 */
export declare function undo<T>(undoableStore: UndoableStore<T>): void;
/**
 * Change the value to the next saved state
 * @param {UndoableStore<*>} undoableStore The store to use
 */
export declare function redo<T>(undoableStore: UndoableStore<T>): void;
/**
 * Indicate if the store value can be revert to a previous state
 * @param {UndoableStore<*>} undoableStore The store to use
 * @return {boolean}
 */
export declare function canUndo<T>(undoableStore: UndoableStore<T>): boolean;
/**
 * Indicate if the store value can be change to a next state
 * @param {UndoableStore<*>} undoableStore The store to use
 * @return {boolean}
 */
export declare function canRedo<T>(undoableStore: UndoableStore<T>): boolean;
/**
 * Revert the value of the store to the oldest state.
 * If the second parameter is `true`, then the store state history is cleared
 * @param {UndoableStore<*>} undoableStore The store to use
 * @param {boolean} clear If `true` the history is cleared
 */
export declare function reset<T>(undoableStore: UndoableStore<T>, clear?: boolean): void;