JavaScript_Succinctly

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Chapter 4 Number() Conceptual overview of using the Number() object The Number() constructor function is used to create numeric objects and numeric primitive values. In the following sample, I detail the creation of numeric values in JavaScript. Sample: sample49.html // Create number object using the new keyword and the Number() constructor. var numberObject = new Number(1); console.log(numberObject); // Logs 1. console.log(typeof numberObject) // Logs 'object'. // Create number literal/primitive using the number constructor without new. var numberObjectWithOutNew = Number(1); // Without using new keyword. console.log(numberObjectWithOutNew); // Logs 1. console.log(typeof numberObjectWithOutNew) // Logs 'number'. // Create number literal/primitive (constructor leveraged behind the scenes). var numberLiteral = 1; console.log(numberLiteral); // Logs 1. console.log(typeof numberLiteral); // Logs 'number'. Integers and floating-point numbers Numbers in JavaScript are typically written as either integer values or floating-point values. In the following code, I create a primitive integer number and a primitive floatingpoint number. This is the most common usage of number values in JavaScript. Sample: sample50.html var integer = 1232134; console.log(integer); // Logs '1232134'. var floatingPoint = 2.132; 64
console.log(floatingPoint); // Logs '2.132'. Notes A numeric value can be a hexadecimal value or octal value in JavaScript, but this is typically not done. Number() parameters The Number() constructor function takes one parameter: the numeric value being created. In the following snippet, we create a number object for the value 456 called numberOne. Sample: sample51.html var numberOne = new Number(456); console.log(numberOne); // Logs '456{}'. Notes When used with the new keyword, instances from the Number() constructor produce a complex object. You should avoid creating number values using the Number() constructor (use literal/primitive numbers) due to the potential problems associated with the typeof operator. The typeof operator reports number objects as 'object' instead of the primitive label ('number') you might expect. The literal/primitive value is just more concise. Number() properties The Number() object has the following properties: Properties (e.g., Number.prototype;) MAX_VALUE MIN_VALUE NaN 65
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By Cody Lindley Foreword by Daniel
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Table of Contents About the Author
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Object() object instance properties
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The Story behind the Succinctly Ser
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About the Author Cody Lindley is a
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Advanced technical books written ab
Page 14 and 15: “Consider that the cody object cr
Page 16 and 17: Chapter 1 JavaScript Objects Creati
Page 18 and 19: Using JavaScript, the getGender met
Page 20 and 21: * The String() constructor function
Page 22 and 23: new object that is returned from th
Page 24 and 25: Notes The Math object is the oddbal
Page 26 and 27: In this snippet, we created a new s
Page 28 and 29: Verify that literals are created fr
Page 30 and 31: The primitive values null, undefine
Page 32 and 33: The concept to take away here is th
Page 34 and 35: * This will throw an error and not
Page 36 and 37: copied, but not the actual value. T
Page 38 and 39: Sample: sample21.html // Primitive
Page 40 and 41: Notes Careful! If you mutate the na
Page 42 and 43: console.log(instanceOfCustomObject.
Page 44 and 45: myObject.prop = 'test'; myArray.pro
Page 46 and 47: Chapter 2 Working with Objects and
Page 48 and 49: Sample: sample31.html // Encapsula
Page 50 and 51: cody['getGender']() // Just slap th
Page 52 and 53: een defined. You might think that b
Page 54 and 55: console.log(myArray.toLocaleString(
Page 56 and 57: Sample: sample44.html var cody = {
Page 58 and 59: Sometimes a web browser manufacture
Page 60 and 61: I like this library because it take
Page 62 and 63: console.log(stringObject); // Logs
Page 66 and 67: NEGATIVE_INFINITY POSITIVE_INFINIT
Page 68 and 69: Parameter passed to Boolean() = Mat
Page 70 and 71: console.log(Boolean(Math)); console
Page 72 and 73: var numberObject = new Number(1.100
Page 74 and 75: Chapter 7 Null Conceptual overview
Page 76 and 77: Chapter 8 Undefined Conceptual over
Page 78 and 79: Chapter 9 The Head/Global Object Co
Page 80 and 81: object. } // Logs bar, foo's value
Page 82 and 83: Make sure you understand that the h
Page 84 and 85: Object() parameters The Object() co
Page 86 and 87: Sample: sample72.html var cody = n
Page 88 and 89: Logs 'foo', being found at Object.p
Page 90 and 91: Sample: sample77.html var addFunct
Page 92 and 93: Sample: sample79.html var yelp = f
Page 94 and 95: parameters when defining the functi
Page 96 and 97: Notes The arguments.length property
Page 98 and 99: Invoking a function (function, meth
Page 100 and 101: Self-invoking anonymous function st
Page 102 and 103: the bar variable. All this is to sh
Page 104 and 105: Chapter 12 The this Keyword Concept
Page 106 and 107: Clearly, the value of this is based
Page 108 and 109: Working around the nested function
Page 110 and 111: What you need to learn here is that
Page 112 and 113: var john = new Person(); // No argu
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Notes An unlimited number of functi
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} (); How is the value of sayHiTex
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var parentFunction = function () {
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Chapter 14 Function Prototype Prope
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Sample: sample119.html var myFunct
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In this example, the foo property i
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console.log(FooInstance.constructor
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Providing a new object as the proto
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var chuck = new Person(0, 0); conso
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An Array() is just a special type o
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It is more common to see an array d
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console.log(myArray.length); // Log
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while (myArrayLength--) { // If len
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ceil() cos() exp() floor() log() ma
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That is: a complex value is equal t
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JavaScript_Succinctly

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