Index • Exploring JavaScript (ES2025 Edition)

A Index

__proto__, #1
--x, #1
x--, #1
-x, #1
, (comma operator), #1
!x, #1
c ? t : e, #1
func?.(«arg0», «arg1», ···), #1
obj?.[«expr»], #1
obj?.prop, #1
x - y, #1
x ??= y, #1
x ?? d, #1
x ** y, #1
x * y, #1
x / y, #1
x && y, #1
x & y, #1
x ٪ y, #1
x ^ y, #1
x + y, #1
x << y, #1
x === y, #1
x >>> y, #1
x >> y, #1
x ¦¦ y, #1
x ¦ y, #1
++x, #1
x++, #1
+x, #1
=, #1
~x, #1

accessor (object literal), #1
addition, #1
AggregateError, #1
AMD module, #1
anonymous function expression, #1
argument, #1
argument vs. parameter, #1
Array, #1
Array hole, #1
Array index, #1
Array literal, #1
Array-destructuring, #1
Array-like object, #1
Array, dense, #1
Array, multidimensional, #1
new Array(), #1
Array, sparse, #1
Array.from(), #1
Array.of(), #1
Array.prototype.at(), #1
Array.prototype.concat(), #1
Array.prototype.copyWithin(), #1
Array.prototype.entries(), #1
Array.prototype.every(), #1
Array.prototype.fill(), #1
Array.prototype.filter(), #1
Array.prototype.find(), #1
Array.prototype.findIndex(), #1
Array.prototype.findLast(), #1
Array.prototype.findLastIndex(), #1
Array.prototype.flat(), #1
Array.prototype.flatMap(), #1
Array.prototype.forEach(), #1
Array.prototype.includes(), #1
Array.prototype.indexOf(), #1
Array.prototype.join(), #1
Array.prototype.keys(), #1
Array.prototype.lastIndexOf(), #1
Array.prototype.map(), #1
Array.prototype.pop(), #1
Array.prototype.push(), #1
Array.prototype.reduce(), #1
Array.prototype.reduceRight(), #1
Array.prototype.reverse(), #1
Array.prototype.shift(), #1
Array.prototype.slice(), #1
Array.prototype.some(), #1
Array.prototype.sort(), #1
Array.prototype.splice(), #1
Array.prototype.toLocaleString(), #1
Array.prototype.toReversed(), #1
Array.prototype.toSorted(), #1
Array.prototype.toSpliced(), #1
Array.prototype.toString(), #1
Array.prototype.unshift(), #1
Array.prototype.values(), #1
Array.prototype.with(), #1
ArrayBuffer, #1
new ArrayBuffer(), #1
ArrayBuffer.isView(), #1
get ArrayBuffer.prototype.byteLength, #1
get ArrayBuffer.prototype.maxByteLength, #1
get ArrayBuffer.prototype.resizable, #1
ArrayBuffer.prototype.resize(), #1
ArrayBuffer.prototype.slice(), #1
Arrays, fixed-layout, #1
Arrays, sequence, #1
arrow function, #1
ASCII escape, #1
ASI (automatic semicolon insertion), #1
assert (module), #1
assert.deepEqual(), #1
assert.equal(), #1
assert.fail(), #1
assert.notDeepEqual(), #1
assert.notEqual(), #1
assert.throws(), #1
assertion, #1
assignment operator, #1
async, #1
async function, #1
async function*, #1
async-await, #1
asynchronous generator, #1
asynchronous iterable, #1
asynchronous iteration, #1
asynchronous iterator, #1
asynchronous programming, #1
attribute of a property, #1
automatic semicolon insertion (ASI), #1
await (async function), #1
await (asynchronous generator), #1

base class, #1
big endian, #1
bigint, #1
BigInt64Array, #1
BigUint64Array, #1
binary integer literal, #1
binding (variable), #1
bitwise And, #1
bitwise Not, #1
bitwise Or, #1
bitwise Xor, #1
boolean, #1
Boolean(), #1
bound variable, #1
break, #1
bundler, #1
bundling, #1

callback (asynchronous pattern), #1
callback function, #1
camel case, #1, #2
case, camel, #1
case, dash, #1
case, kebab, #1
case, snake, #1
case, underscore, #1
catch, #1
class, #1, #2
class declaration, #1
class definition, #1
class expression, #1
class string disjunction, #1
class, base, #1
class, derived, #1
class, mixin, #1
classes, extending, #1
closure, #1
code point, #1
code unit, #1
coercion, #1
combinator function, Promise, #1
comma operator, #1
CommonJS module, #1
comparing by identity, #1
comparing by value, #1
computed property key, #1
concatenating strings, #1
conditional operator, #1
console, #1
console.error(), #1
console.log(), #1
const, #1
constant, #1
constructor function (role of an ordinary function), #1
continue, #1
Converting to [type], #1
converting to primitive, #1
Coordinated Universal Time (UTC), #1

dash case, #1, #2
DataView, #1
new DataView(), #1
get DataView.prototype.buffer, #1
get DataView.prototype.byteLength, #1
get DataView.prototype.byteOffset, #1
DataView.prototype.get(), #1
DataView.prototype.set(), #1
date, #1
date time format, #1
decimal floating point literal, #1
decimal integer literal, #1
decrementation operator (prefix), #1
decrementation operator (suffix), #1
default export, #1
default value (destructuring), #1
default value (parameter), #1
default value operator (??), #1
delete, #1
deleting a property, #1
dense Array, #1
derived class, #1
descriptor of a property, #1
destructive operation, #1
destructuring, #1
destructuring an Array, #1
destructuring an object, #1
dictionary object, #1
direct method call, #1
dispatched method call, #1
divided by operator, #1
division, #1
do-while, #1
dynamic imports, #1
dynamic this, #1
dynamic vs. static, #1

early activation, #1
Ecma, #1
ECMA-262, #1
ECMAScript, #1
ECMAScript module, #1
ECMAScript proposal, #1
Eich, Brendan, #1
endianness (Typed Arrays), #1
enumerability, #1
enumerable (property attribute), #1
equality operator, #1
ES module, #1
escape, ASCII, #1
escape, Unicode code point, #1
escape, Unicode code unit, #1, #2
escaping HTML, #1
eval(), #1
evaluating an expression, #1
event (asynchronous pattern), #1
event loop, #1
exception, #1
exercises, getting started with, #1
exponentiation, #1
export, #1
export default, #1
export, default, #1
export, named, #1
expression, #1
extending classes, #1
extends, #1
external iteration, #1
extracting a method, #1

false, #1
falsiness, #1
falsy, #1
finally, #1
fixed-layout Arrays, #1
fixed-layout object, #1
flags (regular expression), #1
Float16Array, #1
Float32Array, #1
Float64Array, #1
floating point literal, #1
for, #1
for-await-of, #1
for-in, #1
for-of, #1
free variable, #1
fulfilled (Promise state), #1
function declaration, #1
function expression, anonymous, #1
function expression, named, #1
function, arrow, #1
function, ordinary, #1
function, roles of an ordinary, #1
function, specialized, #1
function*, #1

garbage collection, #1
generator, asynchronous, #1
generator, synchronous, #1
getter (object literal), #1
global, #1
global object, #1
global scope, #1
global variable, #1
globalThis, #1
GMT (Greenwich Mean Time), #1
grapheme cluster, #1
Greenwich Mean Time (GMT), #1

hexadecimal integer literal, #1
hoisting, #1
hole in an Array, #1

identifier, #1
identity of an object, #1
if, #1
IIFE (immediately invoked function expression), #1
immediately invoked function expression (IIFE), #1
import, #1
import, named, #1
import, namespace, #1
import.meta, #1
import.meta.url, #1
import(), #1
imports, dynamic, #1
in, #1
incrementation operator (prefix), #1
incrementation operator (suffix), #1
index of an Array, #1
Infinity, #1
inheritance, multiple, #1
inheritance, single, #1
instanceof, #1, #2
Int8Array, #1
Int16Array, #1
Int32Array, #1
integer numbers, #1
integer, safe, #1
internal iteration, #1
iterable (asynchronous), #1
iterable (synchronous), #1
iteration, asynchronous, #1
iteration, external, #1
iteration, internal, #1
iteration, synchronous, #1
iterator (asynchronous), #1
iterator (synchronous), #1
Iterator.prototype.drop(), #1
Iterator.prototype.every(), #1
Iterator.prototype.filter(), #1
Iterator.prototype.find(), #1
Iterator.prototype.flatMap(), #1
Iterator.prototype.forEach(), #1
Iterator.prototype.map(), #1
Iterator.prototype.reduce(), #1
Iterator.prototype.some(), #1
Iterator.prototype.take(), #1
Iterator.prototype.toArray(), #1

JSON (data format), #1
JSON (namespace object), #1

kebab case, #1, #2
keyword, #1

label, #1
leading surrogate, #1
left shift operator, #1
let, #1
lexical this, #1
listing properties, #1
little endian, #1
logical And, #1
logical Not, #1
logical Or, #1
lone surrogate, #1

Map, #1
Map vs. object, #1
new Map(), #1
Map.groupBy(), #1
Map.prototype.clear(), #1
Map.prototype.delete(), #1
Map.prototype.entries(), #1
Map.prototype.forEach(), #1
Map.prototype.get(), #1
Map.prototype.has(), #1
Map.prototype.keys(), #1
Map.prototype.set(), #1
get Map.prototype.size, #1
Map.prototype.values(), #1
Map.prototype[Symbol.iterator](), #1
Math (namespace object), #1
Math.abs(), #1
Math.acos(), #1
Math.acosh(), #1
Math.asin(), #1
Math.asinh(), #1
Math.atan(), #1
Math.atan2(), #1
Math.atanh(), #1
Math.cbrt(), #1
Math.ceil(), #1
Math.clz32(), #1
Math.cos(), #1
Math.cosh(), #1
Math.E(), #1
Math.exp(), #1
Math.expm1(), #1
Math.f16round(), #1
Math.floor(), #1
Math.fround(), #1
Math.hypot(), #1
Math.LN2(), #1
Math.LN10(), #1
Math.log(), #1
Math.log1p(), #1
Math.log2(), #1
Math.LOG2E(), #1
Math.log10(), #1
Math.LOG10E(), #1
Math.max(), #1
Math.min(), #1
Math.PI(), #1
Math.pow(), #1
Math.random(), #1
Math.round(), #1
Math.sign(), #1
Math.sin(), #1
Math.sinh(), #1
Math.sqrt(), #1
Math.SQRT1_2(), #1
Math.SQRT2(), #1
Math.tan(), #1
Math.tanh(), #1
Math.trunc(), #1
method, #1
method (object literal), #1
method (role of an ordinary function), #1
method call, direct, #1
method call, dispatched, #1
method, extracting a, #1
minification, #1
minifier, #1
minus operator (binary), #1
minus operator (unary), #1
mixin class, #1
module specifier, #1
module, AMD, #1
module, CommonJS, #1
multidimensional Array, #1
multiple inheritance, #1
multiple return values, #1
multiplication, #1

named export, #1
named function expression, #1
named import, #1
named parameter, #1
namespace import, #1
NaN, #1
node_modules, #1
non-destructive operation, #1
npm, #1
npm package, #1
null, #1
null prototype object, #1
nullish coalescing assignment operator (??=), #1
nullish coalescing operator (??), #1
number, #1
Number.EPSILON(), #1
Number.isFinite(), #1
Number.isInteger(), #1
Number.isNaN(), #1
Number.isSafeInteger(), #1
Number.MAX_SAFE_INTEGER(), #1
Number.MAX_VALUE(), #1
Number.MIN_SAFE_INTEGER(), #1
Number.MIN_VALUE(), #1
Number.NaN(), #1
Number.NEGATIVE_INFINITY(), #1
Number.parseFloat(), #1
Number.parseInt(), #1
Number.POSITIVE_INFINITY(), #1
Number.prototype.toExponential(), #1
Number.prototype.toFixed(), #1
Number.prototype.toPrecision(), #1
Number.prototype.toString(), #1
Number(), #1

object, #1
object literal, #1
object vs. Map, #1
object vs. primitive value, #1
object-destructuring, #1
object, dictionary, #1
object, fixed-layout, #1
object, identity of an, #1
object, null prototype, #1
Object.assign(), #1
Object.create(), #1
Object.defineProperties(), #1
Object.defineProperty(), #1
Object.entries(), #1
Object.freeze(), #1
Object.fromEntries(), #1
Object.getOwnPropertyDescriptor(), #1
Object.getOwnPropertyDescriptors(), #1
Object.getOwnPropertyNames(), #1
Object.getOwnPropertySymbols(), #1
Object.getPrototypeOf(), #1
Object.groupBy(), #1
Object.hasOwn(), #1
Object.is(), #1, #2
Object.isExtensible(), #1
Object.isFrozen(), #1
Object.isSealed(), #1
Object.keys(), #1
Object.preventExtensions(), #1
Object.prototype methods, #1
Object.prototype.__proto__, #1
get Object.prototype.__proto__, #1
set Object.prototype.__proto__, #1
Object.prototype.hasOwnProperty(), #1, #2
Object.prototype.isPrototypeOf(), #1, #2
Object.prototype.propertyIsEnumerable(), #1, #2
Object.prototype.toLocaleString(), #1, #2
Object.prototype.toString(), #1, #2
Object.prototype.valueOf(), #1, #2
Object.seal(), #1
Object.setPrototypeOf(), #1
Object.values(), #1
Object(), #1
octal integer literal, #1
ones’ complement, #1
operator, assignment, #1
operator, comma, #1
operator, default value (??), #1
operator, equality, #1
operator, nullish coalescing (??), #1
operator, nullish coalescing assignment (??=), #1
operator, void, #1
optional chaining (?.), #1
ordinary function, #1
ordinary function, roles of an, #1
overriding a property, #1

package, #1
package manager, #1
package, npm, #1
package.json, #1
parameter, #1
parameter default value, #1
parameter vs. argument, #1
passing by identity, #1
passing by value, #1
pattern (regular expression), #1
pending (Promise state), #1
plus operator (binary), #1
plus operator (unary), #1
polyfill, #1
polyfill, speculative, #1
ponyfill, #1
primitive value, #1
primitive value vs. object, #1
primitive, converting to, #1
private name, #1
private slot, #1
progressive web app (PWA), #1
prollyfill, #1
Promise, #1, #2
Promise combinator function, #1
new Promise(), #1
Promise, states of a, #1
Promise.all(), #1, #2
Promise.allSettled(), #1, #2
Promise.any(), #1, #2
Promise.prototype.catch(), #1
Promise.prototype.finally(), #1
Promise.prototype.then(), #1
Promise.race(), #1, #2
Promise.reject(), #1
Promise.resolve(), #1
Promise.try(), #1
Promise.withResolvers(), #1
properties, listing, #1
property, #1
property (object), #1
property attribute, #1
property descriptor, #1
property key, #1
property key, computed, #1
property key, quoted, #1
property name, #1
property symbol, #1
property value shorthand, #1
property, deleting a, #1
__proto__, #1
prototype, #1
prototype chain, #1
public slot, #1
publicly known symbol, #1
PWA (progressive web app), #1

quoted property key, #1

real function (role of an ordinary function), #1
receiver, #1
Reflect.apply(), #1
Reflect.construct(), #1
Reflect.defineProperty(), #1
Reflect.deleteProperty(), #1
Reflect.get(), #1
Reflect.getOwnPropertyDescriptor(), #1
Reflect.getPrototypeOf(), #1
Reflect.has(), #1
Reflect.isExtensible(), #1
Reflect.ownKeys(), #1
Reflect.preventExtensions(), #1
Reflect.set(), #1
Reflect.setPrototypeOf(), #1
RegExp, #1
RegExp.prototype.exec(), #1
RegExp.prototype.test(), #1
regular expression, #1
regular expression literal, #1
regular expression string literal, #1
rejected (Promise state), #1
remainder operator, #1
REPL, #1
replica, #1
RequireJS, #1
reserved word, #1
rest element (Array-destructuring), #1
rest parameter (function call), #1
rest property (object-destructuring), #1
return values, multiple, #1
revealing module pattern, #1
roles of an ordinary function, #1
run-to-completion semantics, #1

safe integer, #1
scope of a variable, #1
script, #1
self, #1
sequence Arrays, #1
Set, #1, #2
new Set(), #1
Set.prototype.add(), #1
Set.prototype.clear(), #1
Set.prototype.delete(), #1
Set.prototype.difference(), #1
Set.prototype.entries(), #1
Set.prototype.forEach(), #1
Set.prototype.has(), #1
Set.prototype.intersection(), #1
Set.prototype.isDisjointFrom(), #1
Set.prototype.isSubsetOf(), #1
Set.prototype.isSupersetOf(), #1
Set.prototype.keys(), #1
get Set.prototype.size, #1
Set.prototype.symmetricDifference(), #1
Set.prototype.union(), #1
Set.prototype.values(), #1
Set.prototype[Symbol.iterator](), #1
setter (object literal), #1
settled (Promise state), #1
shadowing, #1
shim, #1
short-circuiting, #1
signed right shift operator, #1
single inheritance, #1
sloppy mode, #1
slot, private, #1
slot, public, #1
snake case, #1, #2
sparse Array, #1
specialized function, #1
specifier, module, #1
speculative polyfill, #1
spreading (...) into a function call, #1
spreading into an Array literal, #1
spreading into an object literal, #1
stack trace, #1
statement, #1
states of a Promise, #1
static, #1
static vs. dynamic, #1
strict mode, #1
string, #1
string literal, regular expression, #1
String.prototype.at(), #1
String.prototype.concat(), #1
String.prototype.endsWith(), #1
String.prototype.includes(), #1
String.prototype.indexOf(), #1
String.prototype.isWellFormed(), #1
String.prototype.lastIndexOf(), #1
String.prototype.match(), #1
String.prototype.matchAll(), #1
String.prototype.normalize(), #1
String.prototype.padEnd(), #1
String.prototype.padStart(), #1
String.prototype.repeat(), #1
String.prototype.replace(), #1
String.prototype.replaceAll(), #1
String.prototype.search(), #1
String.prototype.slice(), #1
String.prototype.split(), #1
String.prototype.startsWith(), #1
String.prototype.substring(), #1
String.prototype.toLowerCase(), #1
String.prototype.toUpperCase(), #1
String.prototype.toWellFormed(), #1
String.prototype.trim(), #1
String.prototype.trimEnd(), #1
String.prototype.trimStart(), #1
String.raw, #1
structuredClone(), #1
subclass, #1
subclassing, #1
subtraction, #1
superclass, #1
surrogate, leading, #1
surrogate, lone, #1
surrogate, trailing, #1
switch, #1
symbol, #1
symbol, publicly known, #1
synchronous generator, #1
synchronous iterable, #1
synchronous iteration, #1
synchronous iterator, #1
syntax, #1

tagged template, #1
task queue, #1
task runner, #1
TC39, #1
TC39 process, #1
TDZ (temporal dead zone), #1
Technical Committee 39, #1
template literal, #1
temporal dead zone, #1
ternary operator, #1
this, #1
this, dynamic, #1
this, lexical, #1
this, values of, #1
throw, #1
time value, #1
times operator, #1
to the power of operator, #1
ToPrimitive, #1
trailing commas in Array literals, #1
trailing commas in object literals, #1
trailing commas in parameter lists, #1
trailing surrogate, #1
transpilation, #1
transpiler, #1
tree-shaking, #1
true, #1
truthiness, #1
truthy, #1
try, #1
type, #1
type hierarchy, #1
type signature, #1
Typed Array, #1
TypedArray.from(), #1
TypedArray.of(), #1
get TypedArray.prototype.buffer, #1
get TypedArray.prototype.byteLength, #1
get TypedArray.prototype.byteOffset, #1
get TypedArray.prototype.length, #1
TypedArray.prototype.set(), #1
TypedArray.prototype.subarray(), #1
typeof, #1
TypeScript, #1

Uint8Array, #1
Uint8ClampedArray, #1
Uint16Array, #1
Uint32Array, #1
undefined, #1
underscore case, #1, #2
Unicode, #1
Unicode code point escape, #1
Unicode code unit escape, #1, #2
Unicode scalar, #1, #2
Unicode Transformation Format (UTF), #1
unit test, #1
unsigned right shift operator, #1
UTC (Coordinated Universal Time), #1
UTF (Unicode Transformation Format), #1
UTF-8, #1
UTF-16, #1
UTF-32, #1

value-preservation, #1
variable, bound, #1
variable, free, #1
variable, scope of a, #1
void operator, #1

Wasm (WebAssembly), #1
WeakMap, #1, #2
WeakSet, #1, #2
Web Worker, #1
WebAssembly, #1
while, #1
window, #1
wrapper class (for a primitive value), #1
wrapper object (for a primitive value), #1

yield (asynchronous generator), #1
yield (synchronous generator), #1
yield* (asynchronous generator), #1
yield* (synchronous generator), #1

Z (Zulu Time Zone), #1
Zulu Time Zone (Z), #1