@wider/utils_proto/proto_number/index.js

A set of extensions to basic objects giving uniform behaviour in various technical environments

'use strict';

const $moduleName = "@wider/utils_proto/proto_number";


/** 
 * Provide extensions to the javascript **Number** prototype
 * @module @wider/utils_proto/proto_number
 * 
 * @copyright Copyright (C) 1985..2021 Martin Baker. http://y-d-r.co.uk
 * @author Martin W Baker
 * @license ISC Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 */


const numberPrototypes = {
    /**
     * always give the n (default 2 hence its chosen name) digits before the decimal place of a number - padding with 0 at left if need be
     * 
     * if number is ***NaN*** then this returns ***aN***
     * @returns {string}
     * @function two()
     */
    wider_two: function(digits) {
        return ("0".repeat(digits || 2) + parseInt(this)).slice(digits || -2);
    },

    /**
     * 
     * fills all the bits lower than the most significant bit with 1's
     * 
     * eg given any value 8 to 15 returns 15 since 2^3 is the most significant bit 100 in binary and so we have binary(1111) = 15 as all the bits
     * 
     * used predominantly in bit implication logics with masks
     * @function bitsUpTo()
     * @returns {BigInteger}
     */
    wider_bitsUpTo: function() {
        let ref = parseInt(this);
        var result = 0;

        while (!isNaN(ref) && ref) {
            ref >>>= 1;
            result = result << 1 | 1;
        }

        return result;
    }
};

/**
 * @private
 * @param {object} target - this will normally be the javascript Function object - but if you dont want to change that object then provide your own equivalent
 */
function assignNumber(target = Number) {

    /* set the prototype of the javascript Function object or if it already exists then extend it */
    if (target.prototype)
        Object.assign(target.prototype, numberPrototypes);
    else
        target.prototype = numberPrototypes;
    
    return numberPrototypes;
}

assignNumber.$moduleName = $moduleName;
if (global.$wider)
    global.$wider.registry.register($moduleName, assignNumber, "protoNumber", "utils");
export default assignNumber;