15.6.1 Boolean as function
2010-07-11
If you call Boolean as a function, the argument will be coerced to a boolean and returned as a primitive. It returns ToBoolean(value).
Note that it would be equivalent to the result of the ! operator.
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15.8.2.2 Math.acos(x)
15.9.5.1 Date.prototype.constructor
15.9.5 Properties of Date.prototype
15.9.4.4 Date.now()
15.9.4.3 Date.UTC(year, month[, date[, hours[, minutes[, seconds[, ms]]]]])
15.9.4.2 Date.parse(string)
15.9.4.1 Date.prototype
15.9.4 Properties of Date constructor
15.9.3.3 new Date()
15.9.3.2 new Date(value)
15.9.3.1 new Date(year, month[, date[, hours[, minutes[, seconds[, ms]]]]])
15.9.3 Date as constructor
15.9.2 Date as a function
15.9.1.15.1 Extended years
15.9.1.15 Date time string format
15.9.1.14 TimeClip(time)
15.9.1.13 MakeDate(day, time)
15.9.1.12 MakeDay(year, month, date)
15.9.1.11 MakeTime(hour, min, sec, ms)
15.9.1.10 Hours, minutes, seconds and milliseconds
15.9.1.9 Local time
15.9.1.8 Daylight saving time adjustment
15.9.1.7 Local time zone adjustment
15.9.1.6 Week day
15.9.1.5 Date number (month day)
15.9.1.4 Month number
15.9.1.3 Year number
15.9.1.2 Day number and time within day
15.9.1.1 Time values and range
15.9.1 Abstract date definitions
15.9 Date object
15.8.2.18 Math.tan(x)
15.8.2.17 Math.sqrt(x)
15.8.2.16 Math.sin(x)
15.8.2.15 Math.round(x)
15.8.2.14 Math.random()
15.8.2.13 Math.pow(x,y)
18.8.2.12 Math.min([value1[, value2[, ... ]]])
15.8.2.11 Math.max([value1[, value2[, ... ]]])
15.8.2.10 Math.log(x)
15.8.2.9 Math.floor(x)
15.8.2.8 Math.exp(x)
15.8.2.7 Math.cos(x)
15.8.2.6 Math.ceil(x)
15.8.2.5 Math.atan2(y, x)
15.8.2.4 Math.atan(x)
15.8.2.3 Math.asin(x)
15.8.2.1 Math.abs(x)
15.8.2 Function properties of Math
15.8.1.8 Math.SQRT2
15.8.1.7 Math.SQRT1_2
15.8.1.6 Math.PI
15.8.1.5 Math.LOG10E
15.8.1.4 Math.LOG2E
15.8.1.3 Math.LN2
15.8.1.2 Math.LN10
15.8.1.1 Math.E
15.8.1 Value properties of Math
15.8 Math object
15.7.5 Properties of Number instances
15.7.4.7 Number.prototype.toPrecision(precision)
15.7.4.6 Number.prototype.toExponential(fractionDigits)
15.7.4.5 Number.prototype.toFixed(fractionDigits)
15.7.4.4 Number.prototype.valueOf()
15.7.4.3 Number.prototype.toLocaleString()
15.7.4.2 Number.prototype.toString([radix])
15.7.4.1 Number.prototype.constructor
15.7.4 Properties of the Number prototype object
15.7.3.6 Number.POSITIVE_INFINITY
15.7.3.5 Number.NEGATIVE_INFINITY
15.7.3.4 Number.NaN
15.7.3.3 Number.MIN_VALUE
15.7.3.2 Number.MAX_VALUE
15.7.3.1 Number.prototype
15.7.3 Properties of the Number constructor
15.7.1 Number as a function
15.7 Number objects
15.6.5 Properties of Boolean instances
15.6.4.3 Boolean.prototype.valueOf()
15.6.4.2 Boolean.prototype.toString()
15.6.4.1 Boolean.prototype.constructor
15.6.3.1 Boolean prototype
15.6.3 Properties of Boolean constructor
15.6.2 Boolean as constructor
15.6.1 Boolean as function
15.6 Boolean objects
15.5.5.2 string.[[GetOwnProperty]](P)
15.5.5.1 string.length
15.5.5 String instance properties
15.5.4.20 String.prototype.trim()
15.5.4.19 String.prototype.toLocaleUpperCase()
15.5.4.18 String.prototype.toUpperCase()
15.5.4.17 String.prototype.toLocaleLowerCase()
15.5.4.16 String.prototype.toLowercase()
15.5.4.15 String.prototype.substring(start, end)
15.5.4.14 String.prototype.split(separator, limit)
15.5.4.13 String.prototype.slice(start,end)
15.5.4.12 String.prototype.seach(regexp)
15.5.4.11 String.prototype.replace(searchValue, replaceValue)
15.5.4.10 String.prototype.match(regexp)
15.5.4.9 String.prototype.localeCompare(that)
15.5.4.8 String.prototype.lastIndexOf(searchString, position)
15.5.4.7 String.prototype.indexOf(searchString, position)
15.5.4.6 String.prototype.concat([string1[, string2[, ... ]]])
15.5.4.5 String.prototype.charCodeAt(pos)
15.5.4.4 String.prototype.charAt(pos)
15.4.3 String.prototype.valueOf()
15.5.4.2 String.prototype.toString()
15.5.4.1 String.prototype.constructor
15.5.4 Properties of the String prototype object
15.5.3.2 String.fromCharCode([char0[, char1[, ...]]])
15.5.3.1 String.prototype
15.5.3 Properties of the String constructor
15.5.2 String constructor
15.5.1 String as a function
15.5 String objects
15.4.5.2 array.length
15.4.5.1 array.[[DefineOwnProperty]](P, Desc, Throw)
15.4.5 Properties of array instances
15.4.4.22 Array.prototype.reduceRight(callbackfn[, initialValue])
15.4.4.21 Array.prototype.reduce(callbackfn[, initialValue])
15.4.4.20 Array.prototype.filter(callbackfn[, thisArg])
15.4.4.19 Array.prototype.map(callbackfn[, thisArg])
15.4.4.18 Array.prototype.foreach(callbackfn[, thisArg])
15.4.4.17 Array.prototype.some(callbackfn[, thisArg])
15.4.4.16 Array.prototype.every(callbackfn[, thisArg])
15.4.4.15 Array.prototype.lastIndexOf(searchElement[, fromIndex])
15.4.4.14 Array.prototype.indexOf(searchElement[, fromIndex])
15.4.4.13 Array.prototype.unshift([item1[, item2[, ... ]]])
15.4.4.12 Array.prototype.splice(start, deleteCount[, item1[, item2[, ... ]]])
15.4.4.11 Array.prototype.sort(comparefn)
15.4.4.10 Array.prototype.slice(start, end)
15.4.4.9 Array.prototype.shift()
15.4.4.8 Array.prototype.reverse()
15.4.4.7 Array.prototype.push([item1[, item2[, ... ]]])
15.4.4.6 Array.prototype.pop()
15.4.4.5 Array.prototype.join(separator)
15.4.4.4 Array.prototype.concat([item1[, item2[, ... ]]])
15.4.4.3 Array.prototype.toLocaleString()
15.4.4.2 Array.prototype.tostring()
15.4.4.1 Array.prototype.constructor
15.4.4 Properties of Array prototype object
15.4.3.2 Array.isArray(arg)
15.4.3.1 Array.prototype
15.4.3 Propertues of the Array Constructor
15.4.2.2 new Array(len)
15.4.2.1 new Array([item0[, item1[, ...]]])
15.4.2 Array constructor
15.4.1 Array as a function
15.4 Array objects
15.3.5.4 [[Get]](P)
15.3.5.3 [[HasInstance]](V)
15.3.5.2 Function.prototype
15.3.5.1 function.length
15.3.5 Properties of function instances
15.3.4.5.3 [[HasInstance]] for bind
15.3.4.5.2 [[Construct]] for bind
15.3.4.5.1 [[Call]] for bind
15.3.4.5 Function.prototype.bind(thisArg[, arg1[, arg2[, ..]]])
15.3.4.4 Function.prototype.call(thisArg[, arg1[, arg2[, ...]]])
15.3.4.3 Function.prototype.apply(thisArg, argArray)
15.3.4.2 Function.prototype.toString()
15.3.4.1 Function.prototype.constructor
15.3.4 Properties of the Function prototype object
15.3.3.1 Function.prototype
15.3.3 Properties of the Function constructor
15.3.2 Function as a constructor
15.3.1 Function as a function
15.3 Function objects
15.2.5 Properties of Object instances
15.2.4.7 Object.prototype.propertyIsEnumerable(V)
15.2.4.6 Object.prototype.isPrototypeOf(V)
15.2.4.5 Object.prototype.hasOwnProperty(V)
15.2.4.4 Object.prototype.valueOf()
15.2.4.3 Object.prototype.toLocaleString()
15.2.4.2 Object.prototype.toString()
15.2.4.1 Object.prototype.constructor
15.2.4 Properties of the Object Prototype Object
15.2.3.14 Object.keys(O)
15.2.3.13 Object.isExtensible(O)
15.2.3.12 Object.isFrozen(O)
15.2.3.11 Object.isSealed(O)
15.2.3.10 Object.preventExtensions(O)
15.2.3.9 Object.freeze(O)
15.2.3.8 Object.seal(O)
15.2.3.7 Object.defineProperties(O, Properties)
15.2.3.6 Object.defineProperty(O, P, Attributes)
15.2.3.5 Object.create(O, Properties)
15.2.3.4 Object.getOwnPropertyNames(O)
15.2.3.3 Object.getOwnPropertyDescriptor(O, P)
15.2.3.2 Object.getPrototypeOf(O)
15.2.3.1 Object.prototype
15.2.3 Properties of the Object constructor
15.2.2 The Object constructor
15.2.1 The Object function
15.2 Object objects
15.1.5 Other properties of the global object
15.1.4 Constructor properties of the global object
15.1.3.4 encodeURIComponent(uriComponent)
15.1.3.3 encodeURI(uri)
15.1.3.2 decodeURIComponent(encodedURIComponent)
15.1.3.1 decodeURI
15.1.3 URI handling function properties
15.1.2.5 isFinite(number)
15.1.2.4 isNaN(number)
15.1.2.3 parseFloat(string)
15.1.2.2 parseInt(string, radix)
15.1.2.1.1 Direct call to eval
15.1.2.1 eval(x)
15.1.2 Function properties of the Global object
15.1.1.3 undefined
15.1.1.2 Infinity
15.1.1.1 NaN
15.1.1 Value properties of the Global object
15.1 Global object
15 Standard built-in Ecmascript objects
14.1 Directive prologue and use strict directive
14 Program
13.2.3 [[ThrowTypeError]]
13.2.2 [[Construct]]
13.2.1 [[Call]]
13.2 Creating function objects
13.1 Strict mode restrictions
13 Function definition
12.15 debugger statement
12.14 try statement
12.13 throw statement
12.11 switch statement
12.10.1 strict mode with
12.10 with statement
12.9 return statement
11.8 break statement
12.7 continue statement
12.6.4 for-in statement
12.6.3 for statement
12.6.2 while statement
12.6.1 do-while statement
12.6 Iteration statements
12.5 If statement
12.4 Expression statement
12.3 Empty statement
12.2.1 Strict mode restrictions
12.2 Variable statement
12.1 Block
12 Statements
11.14 Comma operator ,
11.13.2 Compound assignment op=
11.13.1 Simple assignment
11.13 Assignment operators =
11.12 Conditional operator ?:
11.11 Binary logical operators
11.10 Binary bitwise operators
11.9.6 Strict equality comparison algorithm
11.9.5 Strict does-not-equal operator
11.9.4 Strict equals operator ===
11.9.3 Equality comparison algorithm
11.9.2 Does-not-equals operator !=
11.9.1 Equals operator ==
11.9 Equality Operators
11.8.7 in operator
11.8.6 instanceof operator
11.8.5 Abstract Relational Comparison Algorithm
11.8.4 Greater-than-or-equal operator >=
11.8.3 Less-than-or-equal operator <=
11.8.2 Greater-than operator >
11.8.1 Less-than operator <
11.8 Relational operators
11.7.3 Unsigned right shift operator >>>
11.7.2 Signed right shift operator >>
11.7.1 The Left Shift Operator
11.7 Bitwise Shift Operators
11.6.3 Applying additive operator
11.6.2 Subtraction operator -
11.6.1 The addition operator
11.6 Additive Operators
11.5.3 Applying the % operator
11.5.2 Applying the / operator
11.5.1 Applying the * operator
11.5 Multiplicative Operators
11.4.9 Logical NOT Operator !
11.4.8 bitwise NOT Operator ~
1.4.7 Unary - Operator
1.4.6 Unary + Operator
11.4.5 Prefix decrement operator
11.4.4 Prefix increment operator
11.4.3 typeof operator
11.4.2 void operator
11.4.1 delete operator
11.4 Unary Operators
11.3.2 Postfix Decrement Operator
11.3.1 Postfix Increment Operator
11.3 Postfix Expressions
11.2.5 Function Expressions
11.2.4 Argument Lists
11.2.3 Function calls
11.2.2 New Operator
11.2.1 Property Accessors
11.2 Left-Hand-Side Expressions
11.1.6 Grouping Operator
11.1.5 Object Initialiser
11.1.4 Array Initialiser
11.1.3 Literal Reference
11.1.2 Identifier Reference
11.1.1 this
11.1 Primary Expressions
11 Expressions
10.6 Arguments Object
10.5 Declaration Binding Instantiation
10.4.3 Entering Function Code
10.4.2 Entering Eval Code
10.4.1.1 Initial Global Execution Context
10.4.1 Entering Global Code
10.4 Establishing an execution context
10.3.1 Identifier Resolution
10.3 Execution Contexts
10.2.3 The global environment
10.2.2.3 NewObjectEnvironment
10.2.2.2 NewDeclarativeEnvironment
10.2.2.1 GetIdentifierReference
10.2.2 Lexical Environment Operations
10.2.1.2.6 ImplicitThisValue
10.2.1.2.5 DeleteBinding
10.2.1.2.4 GetBindingValue
10.2.1.2.3 SetMutableBinding
10.2.1.2.2 CreateMutableBinding
10.2.1.2.1 HasBinding
10.2.1.2 Object Environment Records
10.2.1.1.8 InitializeImmutableBinding
10.2.1.1.7 CreateImmutableBinding
10.2.1.1.6 ImplicitThisValue
10.2.1.1.5 DeleteBinding
10.2.1.1.4 GetBindingValue
10.2.1.1.3 SetMutableBinding
10.2.1.1.2 CreateMutableBinding
10.2.1.1.1 HasBinding
10.2.1.1 Declarative Environment Records
10.2.1 Environment Records
10.2 Lexical environments
10.1.1 Strict mode code
10.1 Types of executable code
10 Executable code and execution contexts
9.12 SameValue
9.11 IsCallable
9.10 CheckObjectCoercible
9.9 ToObject
9.8 ToString
9.7 ToUint16
9.6 ToUint32
9.5 ToInt32
9.4 ToInteger
9.3 ToNumber
9.2 ToBoolean
9.1 ToPrimitive
9 Type Conversion and Testing
8.12.9 [[DefineOwnProperty]]
8.12.8 [[DefaultValue]]
8.12.7 [[Delete]]
8.12.6 [[HasProperty]]
8.12.5 Put
8.12.4 CanPut
8.12.3 Get
8.12.2 GetProperty
8.12.1 GetOwnProperty
8.10.5 ToPropertyDescriptor
8.10.4 FromPropertyDescriptor
8.10.1 ~ 3 IsAccessorDescriptor, IsDataDescriptor, IsGenericDescriptor
8.10 Property Descriptor and Identifier
8.9 Completion type
8.8 List type
8.7.2 PutValue
8.7.1 GetValue
8.7 Reference Specification Type
8.6.2.1 For some objects
8.6.2.1 For all objects
8.6.2 Object internal properties and methods
8.6.1 Property Attributes
8.6 Object type
8.5 Number
8.4 String
8.0 Undefined, Null, Boolean
8. Types and Type(x)
7.9 Automatic semicolon insertion
7.8.4 String literals
7.8.3 Numeric Literals
7.8.2 Boolean Literals
7.8.1 Null Literals
7.7 Punctuators
7.6 Reserved words
7.6 Identifiers
7.5 Tokens
7.4 Comments
7.3 Line Terminators
7.2 White Space
7.1 Unicode Format-Control Characters
7 Lexical Conventions
6. Source Text
5. Notational Conventions
Blog conventions