factory-map/dist/FactoryMap.js

Extension of ECMAScript 6 Map to provide default values where no key exists.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
class FactoryMap extends Map {
    constructor(iterableOrDefaultValueFactory, defaultValueFactory) {
        const isFunctionOrUndefined = (f) => iterableOrDefaultValueFactory === undefined || typeof iterableOrDefaultValueFactory === 'function';
        if (isFunctionOrUndefined(iterableOrDefaultValueFactory)) {
            if (iterableOrDefaultValueFactory && defaultValueFactory) {
                throw new Error('Unexpected constructor params');
            }
            super();
            this.factory = iterableOrDefaultValueFactory;
        }
        else {
            super(iterableOrDefaultValueFactory);
            this.factory = defaultValueFactory;
        }
    }
    get(key, defaultValueFactory) {
        let r = super.get(key);
        if (r === undefined) {
            if (defaultValueFactory) {
                r = defaultValueFactory(key);
            }
            else if (this.factory) {
                r = this.factory(key);
            }
            if (r !== undefined) {
                super.set(key, r);
            }
        }
        return r;
    }
}
exports.FactoryMap = FactoryMap;