immutable-js/src/Repeat.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.
 */

import { Sequence } from './Sequence';
import { equal, nullOrUndefined } from './util/is';

export class Repeat extends Sequence {
    constructor(value, repeater) {
        if(!(this instanceof Repeat)) {
            return new Repeat(value, repeater);
        }
        this.__value = value;
        this.size = repeater === undefined ? Infinity : Math.max(0, repeater);
        if(this.size === 0) {
            if(EMPTY_REPEAT) {
                return EMPTY_REPEAT;
            }
            EMPTY_REPEAT = this;
        }
    }

    toString() {
        return this.__toString('Repeat [', this.__value + ' ' + this.size + ' times', ']');
    }

    includes(search) {
        return equal(this.__value, search);
    }

    indexOf(search) {
        if(this.includes(search)) {
            return 0;
        }
        return -1;
    }

    __iterate(handle) {
        for(var ii = 0; ii < this.size; ii++) {
            if(handle(this.__value, ii, this) === false) {
                return ii + 1;
            }
        }
        return ii;
    }

    __ensureOwner(ownerID) {
        if(ownerID === this.__ownerID) {
            return this;
        }
        if(!ownerID || nullOrUndefined(ownerID)) {
            this.__ownerID = ownerID;
            this.__altered = false;
            return this;
        }
        return new Repeat(this.__value, this.size, ownerID);
    }
}

var EMPTY_REPEAT;