immutable-js/src/util/toolset.js

Immutable types in JavaScript

/**
 *  Copyright (c) 2015, Jan Biasi.
 *  All rights reserved.
 *
 *  This source code is licensed under the BSD-style license found in the
 *  LICENSE file in the root directory of this source tree. An additional grant
 *  of patent rights can be found in the PATENTS file in the same directory.
 */

export var TYPEDEF_FIELD = '__type__';
export function typedef(blueprint, prefered) {
    if(typeof blueprint === 'object') {
        if(!blueprint.prototype) {
            return;
        }
        for(var scheme in blueprint) {
            if(scheme && blueprint.hasOwnProperty(scheme)) {
                typedef(blueprint[scheme], scheme);
            }
        }
    } else if(blueprint && typeof prefered === 'string') {
        blueprint.prototype[TYPEDEF_FIELD] = prefered;
    }
}

export function invariant(condition, error) {
    if (!condition) throw new Error(error);
}


/**
 * Contributes additional methods to a constructor
 */
export function mixin(ctor, funcs) {
    var copier = key => { ctor.prototype[key] = funcs[key]; };
    Object.keys(funcs).forEach(copier);
    Object.getOwnPropertySymbols && Object.getOwnPropertySymbols(funcs).forEach(copier);
    return ctor;
}

export function createClass(ctor, superClass) {
    if (superClass) {
      ctor.prototype = Object.create(superClass.prototype);
    }
    ctor.prototype.constructor = ctor;
}