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@f1stnpm2/eligendi-officia-officiis(-pure)

ECMAScript⬆

Modules es.object.assign, es.object.create, es.object.define-getter, es.object.define-property, es.object.define-properties, es.object.define-setter, es.object.entries, es.object.freeze, es.object.from-entries, es.object.get-own-property-descriptor, es.object.get-own-property-descriptors, es.object.get-own-property-names, es.object.get-prototype-of, es.object.group-by, es.object.has-own, es.object.is, es.object.is-extensible, es.object.is-frozen, es.object.is-sealed, es.object.keys, es.object.lookup-setter, es.object.lookup-getter, es.object.prevent-extensions, es.object.proto, es.object.to-string, es.object.seal, es.object.set-prototype-of, es.object.values.

@f1stnpm2/eligendi-officia-officiis(-pure)/es

ECMAScript: Object⬆

class Object {
  toString(): string; // ES2015+ fix: @@toStringTag support
  __defineGetter__(property: PropertyKey, getter: Function): void;
  __defineSetter__(property: PropertyKey, setter: Function): void;
  __lookupGetter__(property: PropertyKey): Function | void;
  __lookupSetter__(property: PropertyKey): Function | void;
  __proto__: Object | null; // required a way setting of prototype - will not in IE10-, it's for modern engines like Deno
  static assign(target: Object, ...sources: Array<Object>): Object;
  static create(prototype: Object | null, properties?: { [property: PropertyKey]: PropertyDescriptor }): Object;
  static defineProperties(object: Object, properties: { [property: PropertyKey]: PropertyDescriptor })): Object;
  static defineProperty(object: Object, property: PropertyKey, attributes: PropertyDescriptor): Object;
  static entries(object: Object): Array<[string, mixed]>;
  static freeze(object: any): any;
  static fromEntries(iterable: Iterable<[key, value]>): Object;
  static getOwnPropertyDescriptor(object: any, property: PropertyKey): PropertyDescriptor | void;
  static getOwnPropertyDescriptors(object: any): { [property: PropertyKey]: PropertyDescriptor };
  static getOwnPropertyNames(object: any): Array<string>;
  static getPrototypeOf(object: any): Object | null;
  static groupBy(items: Iterable, callbackfn: (value: any, index: number) => key): { [key]: Array<mixed> };
  static hasOwn(object: object, key: PropertyKey): boolean;
  static is(value1: any, value2: any): boolean;
  static isExtensible(object: any): boolean;
  static isFrozen(object: any): boolean;
  static isSealed(object: any): boolean;
  static keys(object: any): Array<string>;
  static preventExtensions(object: any): any;
  static seal(object: any): any;
  static setPrototypeOf(target: any, prototype: Object | null): any; // required __proto__ - IE11+
  static values(object: any): Array<mixed>;
}

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/assign
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/is
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/set-prototype-of
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/get-prototype-of
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/create
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/define-property
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/define-properties
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/get-own-property-descriptor
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/get-own-property-descriptors
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/group-by
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/has-own
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/keys
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/values
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/entries
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/get-own-property-names
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/freeze
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/from-entries
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/seal
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/prevent-extensions
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/object/proto
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/is-frozen
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/is-sealed
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/is-extensible
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/object/to-string
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/define-getter
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/define-setter
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/lookup-getter
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/lookup-setter

Examples:

let foo = { q: 1, w: 2 };
let bar = { e: 3, r: 4 };
let baz = { t: 5, y: 6 };
Object.assign(foo, bar, baz); // => foo = { q: 1, w: 2, e: 3, r: 4, t: 5, y: 6 }

Object.is(NaN, NaN); // => true
Object.is(0, -0);    // => false
Object.is(42, 42);   // => true
Object.is(42, '42'); // => false

function Parent() {}
function Child() {}
Object.setPrototypeOf(Child.prototype, Parent.prototype);
new Child() instanceof Child;  // => true
new Child() instanceof Parent; // => true

let object = {
  [Symbol.toStringTag]: 'Foo'
};

'' + object; // => '[object Foo]'

Object.keys('qwe'); // => ['0', '1', '2']
Object.getPrototypeOf('qwe') === String.prototype; // => true

Object.values({ a: 1, b: 2, c: 3 });  // => [1, 2, 3]
Object.entries({ a: 1, b: 2, c: 3 }); // => [['a', 1], ['b', 2], ['c', 3]]

for (let [key, value] of Object.entries({ a: 1, b: 2, c: 3 })) {
  console.log(key);   // => 'a', 'b', 'c'
  console.log(value); // => 1, 2, 3
}

// Shallow object cloning with prototype and descriptors:
let copy = Object.create(Object.getPrototypeOf(object), Object.getOwnPropertyDescriptors(object));
// Mixin:
Object.defineProperties(target, Object.getOwnPropertyDescriptors(source));

const map = new Map([['a', 1], ['b', 2]]);
Object.fromEntries(map); // => { a: 1, b: 2 }

class Unit {
  constructor(id) {
    this.id = id;
  }
  toString() {
    return `unit${ this.id }`;
  }
}

const units = new Set([new Unit(101), new Unit(102)]);

Object.fromEntries(units.entries()); // => { unit101: Unit { id: 101 }, unit102: Unit { id: 102 } }

Object.hasOwn({ foo: 42 }, 'foo'); // => true
Object.hasOwn({ foo: 42 }, 'bar'); // => false
Object.hasOwn({}, 'toString');     // => false

Object.groupBy([1, 2, 3, 4, 5], it => it % 2); // => { 1: [1, 3, 5], 0: [2, 4] }

ECMAScript: Function⬆

Modules es.function.name, es.function.has-instance. Just ES5: es.function.bind.

class Function {
  name: string;
  bind(thisArg: any, ...args: Array<mixed>): Function;
  @@hasInstance(value: any): boolean;
}

@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/function
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/function/name
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/function/has-instance
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/function/bind
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/function/virtual/bind

(function foo() {}).name // => 'foo'

console.log.bind(console, 42)(43); // => 42 43

ECMAScript: Error⬆

Modules es.aggregate-error, es.aggregate-error.cause, es.error.cause, es.error.to-string.

class [
  Error,
  EvalError,
  RangeError,
  ReferenceError,
  SyntaxError,
  TypeError,
  URIError,
  WebAssembly.CompileError,
  WebAssembly.LinkError,
  WebAssembly.RuntimeError,
] {
  constructor(message: string, { cause: any }): %Error%;
}

class AggregateError extends Error {
  constructor(errors: Iterable, message?: string, { cause: any }?): AggregateError;
  errors: Array<any>;
  message: string;
  cause: any;
}

class Error {
  toString(): string; // different fixes
}

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/aggregate-error
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/error
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/error/constructor
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/error/to-string

const error1 = new TypeError('Error 1');
const error2 = new TypeError('Error 2');
const aggregate = new AggregateError([error1, error2], 'Collected errors');
aggregate.errors[0] === error1; // => true
aggregate.errors[1] === error2; // => true

const cause = new TypeError('Something wrong');
const error = new TypeError('Here explained what`s wrong', { cause });
error.cause === cause; // => true

Error.prototype.toString.call({ message: 1, name: 2 }) === '2: 1'; // => true

ECMAScript: Array⬆

Modules es.array.from, es.array.is-array, es.array.of, es.array.copy-within, es.array.fill, es.array.find, es.array.find-index, es.array.find-last, es.array.find-last-index, es.array.iterator, es.array.includes, es.array.push, es.array.slice, es.array.join, es.array.unshift, es.array.index-of, es.array.last-index-of, es.array.every, es.array.some, es.array.for-each, es.array.map, es.array.filter, es.array.reduce, es.array.reduce-right, es.array.reverse, es.array.sort, es.array.flat, es.array.flat-map, es.array.unscopables.flat, es.array.unscopables.flat-map, es.array.at, es.array.to-reversed, es.array.to-sorted, es.array.to-spliced, es.array.with.

class Array {
  at(index: int): any;
  concat(...args: Array<mixed>): Array<mixed>; // with adding support of @@isConcatSpreadable and @@species
  copyWithin(target: number, start: number, end?: number): this;
  entries(): Iterator<[index, value]>;
  every(callbackfn: (value: any, index: number, target: any) => boolean, thisArg?: any): boolean;
  fill(value: any, start?: number, end?: number): this;
  filter(callbackfn: (value: any, index: number, target: any) => boolean, thisArg?: any): Array<mixed>; // with adding support of @@species
  find(callbackfn: (value: any, index: number, target: any) => boolean), thisArg?: any): any;
  findIndex(callbackfn: (value: any, index: number, target: any) => boolean, thisArg?: any): uint;
  findLast(callbackfn: (value: any, index: number, target: any) => boolean, thisArg?: any): any;
  findLastIndex(callbackfn: (value: any, index: number, target: any) => boolean, thisArg?: any): uint;
  flat(depthArg?: number = 1): Array<mixed>;
  flatMap(mapFn: (value: any, index: number, target: any) => any, thisArg: any): Array<mixed>;
  forEach(callbackfn: (value: any, index: number, target: any) => void, thisArg?: any): void;
  includes(searchElement: any, from?: number): boolean;
  indexOf(searchElement: any, from?: number): number;
  join(separator: string = ','): string;
  keys(): Iterator<index>;
  lastIndexOf(searchElement: any, from?: number): number;
  map(mapFn: (value: any, index: number, target: any) => any, thisArg?: any): Array<mixed>; // with adding support of @@species
  push(...args: Array<mixed>): uint;
  reduce(callbackfn: (memo: any, value: any, index: number, target: any) => any, initialValue?: any): any;
  reduceRight(callbackfn: (memo: any, value: any, index: number, target: any) => any, initialValue?: any): any;
  reverse(): this; // Safari 12.0 bug fix
  slice(start?: number, end?: number): Array<mixed>; // with adding support of @@species
  splice(start?: number, deleteCount?: number, ...items: Array<mixed>): Array<mixed>; // with adding support of @@species
  some(callbackfn: (value: any, index: number, target: any) => boolean, thisArg?: any): boolean;
  sort(comparefn?: (a: any, b: any) => number): this; // with modern behavior like stable sort
  toReversed(): Array<mixed>;
  toSpliced(start?: number, deleteCount?: number, ...items: Array<mixed>): Array<mixed>;
  toSorted(comparefn?: (a: any, b: any) => number): Array<mixed>;
  unshift(...args: Array<mixed>): uint;
  values(): Iterator<value>;
  with(index: includes, value: any): Array<mixed>;
  @@iterator(): Iterator<value>;
  @@unscopables: { [newMethodNames: string]: true };
  static from(items: Iterable | ArrayLike, mapFn?: (value: any, index: number) => any, thisArg?: any): Array<mixed>;
  static isArray(value: any): boolean;
  static of(...args: Array<mixed>): Array<mixed>;
}

class Arguments {
  @@iterator(): Iterator<value>; // available only in @f1stnpm2/eligendi-officia-officiis methods
}

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array/from
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array/of
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array/is-array
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/at
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/concat
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/copy-within
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/entries
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/every
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/fill
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/filter
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/find
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/find-index
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/find-last
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/find-last-index
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/flat
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/flat-map
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/for-each
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/includes
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/index-of
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/iterator
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/join
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/keys
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/last-index-of
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/map
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/push
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/reduce
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/reduce-right
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/reverse
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/slice
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/some
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/sort
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/splice
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/to-reversed
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/to-sorted
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/to-spliced
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/unshift
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/values
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/with

Array.from(new Set([1, 2, 3, 2, 1]));        // => [1, 2, 3]
Array.from({ 0: 1, 1: 2, 2: 3, length: 3 }); // => [1, 2, 3]
Array.from('123', Number);                   // => [1, 2, 3]
Array.from('123', it => it * it);            // => [1, 4, 9]

Array.of(1);       // => [1]
Array.of(1, 2, 3); // => [1, 2, 3]

let array = ['a', 'b', 'c'];

for (let value of array) console.log(value);          // => 'a', 'b', 'c'
for (let value of array.values()) console.log(value); // => 'a', 'b', 'c'
for (let key of array.keys()) console.log(key);       // => 0, 1, 2
for (let [key, value] of array.entries()) {
  console.log(key);                                   // => 0, 1, 2
  console.log(value);                                 // => 'a', 'b', 'c'
}

function isOdd(value) {
  return value % 2;
}
[4, 8, 15, 16, 23, 42].find(isOdd);      // => 15
[4, 8, 15, 16, 23, 42].findIndex(isOdd); // => 2
[1, 2, 3, 4].findLast(isOdd);            // => 3
[1, 2, 3, 4].findLastIndex(isOdd);       // => 2

Array(5).fill(42); // => [42, 42, 42, 42, 42]

[1, 2, 3, 4, 5].copyWithin(0, 3); // => [4, 5, 3, 4, 5]


[1, 2, 3].includes(2);        // => true
[1, 2, 3].includes(4);        // => false
[1, 2, 3].includes(2, 2);     // => false

[NaN].indexOf(NaN);           // => -1
[NaN].includes(NaN);          // => true
Array(1).indexOf(undefined);  // => -1
Array(1).includes(undefined); // => true

[1, [2, 3], [4, 5]].flat();    // => [1, 2, 3, 4, 5]
[1, [2, [3, [4]]], 5].flat();  // => [1, 2, [3, [4]], 5]
[1, [2, [3, [4]]], 5].flat(3); // => [1, 2, 3, 4, 5]

[{ a: 1, b: 2 }, { a: 3, b: 4 }, { a: 5, b: 6 }].flatMap(it => [it.a, it.b]); // => [1, 2, 3, 4, 5, 6]

[1, 2, 3].at(1);  // => 2
[1, 2, 3].at(-1); // => 3

const sequence = [1, 2, 3];
sequence.toReversed(); // => [3, 2, 1]
sequence; // => [1, 2, 3]

const array = [1, 2, 3, 4];
array.toSpliced(1, 2, 5, 6, 7); // => [1, 5, 6, 7, 4]
array; // => [1, 2, 3, 4]

const outOfOrder = [3, 1, 2];
outOfOrder.toSorted(); // => [1, 2, 3]
outOfOrder; // => [3, 1, 2]

const correctionNeeded = [1, 1, 3];
correctionNeeded.with(1, 2); // => [1, 2, 3]
correctionNeeded; // => [1, 1, 3]

ECMAScript: String and RegExp⬆

The main part of String features: modules es.string.from-code-point, es.string.raw, es.string.iterator, es.string.split, es.string.code-point-at, es.string.ends-with, es.string.includes, es.string.repeat, es.string.pad-start, es.string.pad-end, es.string.starts-with, es.string.trim, es.string.trim-start, es.string.trim-end, es.string.match-all, es.string.replace-all, es.string.at-alternative, es.string.is-well-formed, es.string.to-well-formed.

Adding support of well-known symbols @@match, @@replace, @@search and @@split and direct .exec calls to related String methods, modules es.string.match, es.string.replace, es.string.search and es.string.split.

Annex B methods. Modules es.string.anchor, es.string.big, es.string.blink, es.string.bold, es.string.fixed, es.string.fontcolor, es.string.fontsize, es.string.italics, es.string.link, es.string.small, es.string.strike, es.string.sub, es.string.sup, es.string.substr, es.escape and es.unescape.

RegExp features: modules es.regexp.constructor, es.regexp.dot-all, es.regexp.flags, es.regexp.sticky and es.regexp.test.

class String {
  static fromCodePoint(...codePoints: Array<number>): string;
  static raw({ raw: Array<string> }, ...substitutions: Array<string>): string;
  at(index: int): string;
  includes(searchString: string, position?: number): boolean;
  startsWith(searchString: string, position?: number): boolean;
  endsWith(searchString: string, position?: number): boolean;
  repeat(count: number): string;
  padStart(length: number, fillStr?: string = ' '): string;
  padEnd(length: number, fillStr?: string = ' '): string;
  codePointAt(pos: number): number | void;
  match(template: any): any; // ES2015+ fix for support @@match
  matchAll(regexp: RegExp): Iterator;
  replace(template: any, replacer: any): any; // ES2015+ fix for support @@replace
  replaceAll(searchValue: string | RegExp, replaceString: string | (searchValue, index, this) => string): string;
  search(template: any): any; // ES2015+ fix for support @@search
  split(template: any, limit?: int): Array<string>;; // ES2015+ fix for support @@split, some fixes for old engines
  trim(): string;
  trimLeft(): string;
  trimRight(): string;
  trimStart(): string;
  trimEnd(): string;
  isWellFormed(): boolean;
  toWellFormed(): string;
  anchor(name: string): string;
  big(): string;
  blink(): string;
  bold(): string;
  fixed(): string;
  fontcolor(color: string): string;
  fontsize(size: any): string;
  italics(): string;
  link(url: string): string;
  small(): string;
  strike(): string;
  sub(): string;
  substr(start: int, length?: int): string;
  sup(): string;
  @@iterator(): Iterator<characters>;
}

class RegExp {
  // support of sticky (`y`) flag, dotAll (`s`) flag, named capture groups, can alter flags
  constructor(pattern: RegExp | string, flags?: string): RegExp;
  exec(): Array<string | undefined> | null; // IE8 fixes
  test(string: string): boolean; // delegation to `.exec`
  toString(): string; // ES2015+ fix - generic
  @@match(string: string): Array | null;
  @@matchAll(string: string): Iterator;
  @@replace(string: string, replaceValue: Function | string): string;
  @@search(string: string): number;
  @@split(string: string, limit: number): Array<string>;
  readonly attribute dotAll: boolean; // IE9+
  readonly attribute flags: string;   // IE9+
  readonly attribute sticky: boolean; // IE9+
}

function escape(string: string): string;
function unescape(string: string): string;

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string/from-code-point
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string/raw
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/string/match
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/string/replace
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/string/search
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/string/split
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual/string(/virtual)/at
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/code-point-at
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/ends-with
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/includes
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/starts-with
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/match-all
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/pad-start
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/pad-end
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/repeat
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/replace-all
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/trim
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/trim-start
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/trim-end
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/trim-left
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/trim-right
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/is-well-formed
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/to-well-formed
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/anchor
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/big
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/blink
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/bold
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/fixed
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/fontcolor
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/fontsize
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/italics
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/link
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/small
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/strike
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/sub
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/substr
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/sup
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/string(/virtual)/iterator
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/regexp
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/regexp/constructor
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/regexp/dot-all
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/regexp/flags
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/regexp/sticky
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/regexp/test
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/regexp/to-string
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/escape
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/unescape

for (let value of 'a𠮷b') {
  console.log(value); // => 'a', '𠮷', 'b'
}

'foobarbaz'.includes('bar');      // => true
'foobarbaz'.includes('bar', 4);   // => false
'foobarbaz'.startsWith('foo');    // => true
'foobarbaz'.startsWith('bar', 3); // => true
'foobarbaz'.endsWith('baz');      // => true
'foobarbaz'.endsWith('bar', 6);   // => true

'string'.repeat(3); // => 'stringstringstring'

'hello'.padStart(10);         // => '     hello'
'hello'.padStart(10, '1234'); // => '12341hello'
'hello'.padEnd(10);           // => 'hello     '
'hello'.padEnd(10, '1234');   // => 'hello12341'

'𠮷'.codePointAt(0); // => 134071
String.fromCodePoint(97, 134071, 98); // => 'a𠮷b'

let name = 'Bob';
String.raw`Hi\n${name}!`;             // => 'Hi\\nBob!' (ES2015 template string syntax)
String.raw({ raw: 'test' }, 0, 1, 2); // => 't0e1s2t'

'foo'.bold();                      // => '<b>foo</b>'
'bar'.anchor('a"b');               // => '<a name="a&quot;b">bar</a>'
'baz'.link('https://example.com'); // => '<a href="https://example.com">baz</a>'

RegExp('.', 's').test('\n'); // => true
RegExp('.', 's').dotAll;     // => true

RegExp('foo:(?<foo>\\w+),bar:(?<bar>\\w+)').exec('foo:abc,bar:def').groups.bar; // => 'def'

'foo:abc,bar:def'.replace(RegExp('foo:(?<foo>\\w+),bar:(?<bar>\\w+)'), '$<bar>,$<foo>'); // => 'def,abc'

RegExp(/./g, 'm'); // => /./m

/foo/.flags;    // => ''
/foo/gim.flags; // => 'gim'

RegExp('foo', 'y').sticky; // => true

const text = 'First line\nSecond line';
const regex = RegExp('(\\S+) line\\n?', 'y');

regex.exec(text)[1]; // => 'First'
regex.exec(text)[1]; // => 'Second'
regex.exec(text);    // => null

'foo'.match({ [Symbol.match]: () => 1 });     // => 1
'foo'.replace({ [Symbol.replace]: () => 2 }); // => 2
'foo'.search({ [Symbol.search]: () => 3 });   // => 3
'foo'.split({ [Symbol.split]: () => 4 });     // => 4

RegExp.prototype.toString.call({ source: 'foo', flags: 'bar' }); // => '/foo/bar'

'   hello   '.trimLeft();  // => 'hello   '
'   hello   '.trimRight(); // => '   hello'
'   hello   '.trimStart(); // => 'hello   '
'   hello   '.trimEnd();   // => '   hello'

for (let [_, d, D] of '1111a2b3cccc'.matchAll(/(\d)(\D)/g)) {
  console.log(d, D); // => 1 a, 2 b, 3 c
}

'Test abc test test abc test.'.replaceAll('abc', 'foo'); // -> 'Test foo test test foo test.'

'abc'.at(1);  // => 'b'
'abc'.at(-1); // => 'c'

'a💩b'.isWellFormed();      // => true
'a\uD83Db'.isWellFormed();  // => false

'a💩b'.toWellFormed();      // => 'a💩b'
'a\uD83Db'.toWellFormed();  // => 'a�b'

ECMAScript: Number⬆

Module es.number.constructor. Number constructor support binary and octal literals, example:

Number('0b1010101'); // => 85
Number('0o7654321'); // => 2054353

Modules es.number.epsilon, es.number.is-finite, es.number.is-integer, es.number.is-nan, es.number.is-safe-integer, es.number.max-safe-integer, es.number.min-safe-integer, es.number.parse-float, es.number.parse-int, es.number.to-exponential, es.number.to-fixed, es.number.to-precision, es.parse-int, es.parse-float.

class Number {
  constructor(value: any): number;
  toExponential(digits: number): string;
  toFixed(digits: number): string;
  toPrecision(precision: number): string;
  static isFinite(number: any): boolean;
  static isNaN(number: any): boolean;
  static isInteger(number: any): boolean;
  static isSafeInteger(number: any): boolean;
  static parseFloat(string: string): number;
  static parseInt(string: string, radix?: number = 10): number;
  static EPSILON: number;
  static MAX_SAFE_INTEGER: number;
  static MIN_SAFE_INTEGER: number;
}

function parseFloat(string: string): number;
function parseInt(string: string, radix?: number = 10): number;

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/number
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/number/constructor
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/number/is-finite
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/number/is-nan
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/number/is-integer
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/number/is-safe-integer
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/number/parse-float
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/number/parse-int
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/number/epsilon
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/number/max-safe-integer
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/number/min-safe-integer
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/number(/virtual)/to-exponential
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/number(/virtual)/to-fixed
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/number(/virtual)/to-precision
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/parse-float
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/parse-int

ECMAScript: Math⬆

Modules es.math.acosh, es.math.asinh, es.math.atanh, es.math.cbrt, es.math.clz32, es.math.cosh, es.math.expm1, es.math.fround, es.math.hypot, es.math.imul, es.math.log10, es.math.log1p, es.math.log2, es.math.sign, es.math.sinh, es.math.tanh, es.math.trunc.

namespace Math {
  acosh(number: number): number;
  asinh(number: number): number;
  atanh(number: number): number;
  cbrt(number: number): number;
  clz32(number: number): number;
  cosh(number: number): number;
  expm1(number: number): number;
  fround(number: number): number;
  hypot(...args: Array<number>): number;
  imul(number1: number, number2: number): number;
  log1p(number: number): number;
  log10(number: number): number;
  log2(number: number): number;
  sign(number: number): 1 | -1 | 0 | -0 | NaN;
  sinh(number: number): number;
  tanh(number: number): number;
  trunc(number: number): number;
}

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/acosh
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/asinh
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/atanh
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/cbrt
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/clz32
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/cosh
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/expm1
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/fround
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/hypot
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/imul
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/log1p
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/log10
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/log2
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/sign
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/sinh
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/tanh
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/trunc

ECMAScript: Date⬆

Modules es.date.to-string, ES5 features with fixes: es.date.now, es.date.to-iso-string, es.date.to-json and es.date.to-primitive.

Annex B methods. Modules es.date.get-year, es.date.set-year and es.date.to-gmt-string.

class Date {
  getYear(): int;
  setYear(year: int): number;
  toGMTString(): string;
  toISOString(): string;
  toJSON(): string;
  toString(): string;
  @@toPrimitive(hint: 'default' | 'number' | 'string'): string | number;
  static now(): number;
}

@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/date
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/date/to-string
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/date/now
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/date/get-year
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/date/set-year
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/date/to-gmt-string
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/date/to-iso-string
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/date/to-json
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/date/to-primitive

new Date(NaN).toString(); // => 'Invalid Date'

ECMAScript: Promise⬆

Modules es.promise, es.promise.all-settled, es.promise.any, es.promise.finally and es.promise.with-resolvers.

class Promise {
  constructor(executor: (resolve: Function, reject: Function) => void): Promise;
  then(onFulfilled: Function, onRejected: Function): Promise;
  catch(onRejected: Function): Promise;
  finally(onFinally: Function): Promise;
  static all(iterable: Iterable): Promise;
  static allSettled(iterable: Iterable): Promise;
  static any(promises: Iterable): Promise;
  static race(iterable: Iterable): Promise;
  static reject(r: any): Promise;
  static resolve(x: any): Promise;
  static withResolvers(): { promise: Promise, resolve: function, reject: function };
}

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/promise
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/promise/all-settled
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/promise/any
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/promise/finally
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/promise/with-resolvers

Basic example:

function sleepRandom(time) {
  return new Promise((resolve, reject) => {
    setTimeout(resolve, time * 1e3, 0 | Math.random() * 1e3);
  });
}

console.log('Run');                    // => Run
sleepRandom(5).then(result => {
  console.log(result);                 // => 869, after 5 sec.
  return sleepRandom(10);
}).then(result => {
  console.log(result);                 // => 202, after 10 sec.
}).then(() => {
  console.log('immediately after');    // => immediately after
  throw Error('Irror!');
}).then(() => {
  console.log('will not be displayed');
}).catch(x => console.log(x));         // => => Error: Irror!

Promise.resolve and Promise.reject example:

Promise.resolve(42).then(x => console.log(x)); // => 42
Promise.reject(42).catch(x => console.log(x)); // => 42

Promise.resolve($.getJSON('/data.json')); // => ES promise

Promise#finally example:

Promise.resolve(42).finally(() => console.log('You will see it anyway'));

Promise.reject(42).finally(() => console.log('You will see it anyway'));

Promise.all example:

Promise.all([
  'foo',
  sleepRandom(5),
  sleepRandom(15),
  sleepRandom(10)             // after 15 sec:
]).then(x => console.log(x)); // => ['foo', 956, 85, 382]

Promise.race example:

function timeLimit(promise, time) {
  return Promise.race([promise, new Promise((resolve, reject) => {
    setTimeout(reject, time * 1e3, Error('Await > ' + time + ' sec'));
  })]);
}

timeLimit(sleepRandom(5), 10).then(x => console.log(x));   // => 853, after 5 sec.
timeLimit(sleepRandom(15), 10).catch(x => console.log(x)); // Error: Await > 10 sec

Promise.allSettled example:

Promise.allSettled([
  Promise.resolve(1),
  Promise.reject(2),
  Promise.resolve(3),
]).then(console.log); // => [{ value: 1, status: 'fulfilled' }, { reason: 2, status: 'rejected' }, { value: 3, status: 'fulfilled' }]

Promise.any example:

Promise.any([
  Promise.resolve(1),
  Promise.reject(2),
  Promise.resolve(3),
]).then(console.log); // => 1

Promise.any([
  Promise.reject(1),
  Promise.reject(2),
  Promise.reject(3),
]).catch(({ errors }) => console.log(errors)); // => [1, 2, 3]

Promise.withResolvers examples:

const d = Promise.withResolvers();
d.resolve(42);
d.promise.then(console.log); // => 42

Example with async functions:

let delay = time => new Promise(resolve => setTimeout(resolve, time))

async function sleepRandom(time) {
  await delay(time * 1e3);
  return 0 | Math.random() * 1e3;
}

async function sleepError(time, msg) {
  await delay(time * 1e3);
  throw Error(msg);
}

(async () => {
  try {
    console.log('Run');                // => Run
    console.log(await sleepRandom(5)); // => 936, after 5 sec.
    let [a, b, c] = await Promise.all([
      sleepRandom(5),
      sleepRandom(15),
      sleepRandom(10)
    ]);
    console.log(a, b, c);              // => 210 445 71, after 15 sec.
    await sleepError(5, 'Error!');
    console.log('Will not be displayed');
  } catch (e) {
    console.log(e);                    // => Error: 'Error!', after 5 sec.
  }
})();

Unhandled rejection tracking⬆

In Node.js, like in native implementation, available events unhandledRejection and rejectionHandled:

process.on('unhandledRejection', (reason, promise) => console.log('unhandled', reason, promise));
process.on('rejectionHandled', (promise) => console.log('handled', promise));

let promise = Promise.reject(42);
// unhandled 42 [object Promise]

setTimeout(() => promise.catch(() => {}), 1e3);
// handled [object Promise]

In a browser on rejection, by default, you will see notify in the console, or you can add a custom handler and a handler on handling unhandled, example:

window.addEventListener('unhandledrejection', e => console.log('unhandled', e.reason, e.promise));
window.addEventListener('rejectionhandled', e => console.log('handled', e.reason, e.promise));
// or
window.onunhandledrejection = e => console.log('unhandled', e.reason, e.promise);
window.onrejectionhandled = e => console.log('handled', e.reason, e.promise);

let promise = Promise.reject(42);
// => unhandled 42 [object Promise]

setTimeout(() => promise.catch(() => {}), 1e3);
// => handled 42 [object Promise]

ECMAScript: Symbol⬆

Modules es.symbol, es.symbol.async-iterator, es.symbol.description, es.symbol.has-instance, es.symbol.is-concat-spreadable, es.symbol.iterator, es.symbol.match, es.symbol.replace, es.symbol.search, es.symbol.species, es.symbol.split, es.symbol.to-primitive, es.symbol.to-string-tag, es.symbol.unscopables, es.math.to-string-tag.

class Symbol {
  constructor(description?): symbol;
  readonly attribute description: string | void;
  static asyncIterator: @@asyncIterator;
  static hasInstance: @@hasInstance;
  static isConcatSpreadable: @@isConcatSpreadable;
  static iterator: @@iterator;
  static match: @@match;
  static replace: @@replace;
  static search: @@search;
  static species: @@species;
  static split: @@split;
  static toPrimitive: @@toPrimitive;
  static toStringTag: @@toStringTag;
  static unscopables: @@unscopables;
  static for(key: string): symbol;
  static keyFor(sym: symbol): string;
  static useSimple(): void;
  static useSetter(): void;
}

class Object {
  static getOwnPropertySymbols(object: any): Array<symbol>;
}

Also wrapped some methods for correct work with Symbol polyfill.

class Object {
  static create(prototype: Object | null, properties?: { [property: PropertyKey]: PropertyDescriptor }): Object;
  static defineProperties(object: Object, properties: { [property: PropertyKey]: PropertyDescriptor })): Object;
  static defineProperty(object: Object, property: PropertyKey, attributes: PropertyDescriptor): Object;
  static getOwnPropertyDescriptor(object: any, property: PropertyKey): PropertyDescriptor | void;
  static getOwnPropertyNames(object: any): Array<string>;
  propertyIsEnumerable(key: PropertyKey): boolean;
}

Symbol#description getter:

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol/async-iterator
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/symbol/description
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol/has-instance
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol/is-concat-spreadable
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol/iterator
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol/match
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol/replace
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol/search
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol/species
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol/split
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol/to-primitive
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol/to-string-tag
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol/unscopables
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol/for
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/symbol/key-for
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/object/get-own-property-symbols
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/math/to-string-tag

Basic example:

let Person = (() => {
  let NAME = Symbol('name');
  return class {
    constructor(name) {
      this[NAME] = name;
    }
    getName() {
      return this[NAME];
    }
  }
})();

let person = new Person('Vasya');
console.log(person.getName());            // => 'Vasya'
console.log(person['name']);              // => undefined
console.log(person[Symbol('name')]);      // => undefined, symbols are uniq
for (let key in person) console.log(key); // => nothing, symbols are not enumerable

Symbol.for & Symbol.keyFor example:

let symbol = Symbol.for('key');
symbol === Symbol.for('key'); // true
Symbol.keyFor(symbol);        // 'key'

Example with methods for getting own object keys:

let object = { a: 1 };
Object.defineProperty(object, 'b', { value: 2 });
object[Symbol('c')] = 3;
Object.keys(object);                  // => ['a']
Object.getOwnPropertyNames(object);   // => ['a', 'b']
Object.getOwnPropertySymbols(object); // => [Symbol(c)]
Reflect.ownKeys(object);              // => ['a', 'b', Symbol(c)]

Symbol('foo').description; // => 'foo'
Symbol().description;      // => undefined

Caveats when using `Symbol` polyfill:⬆

We can't add new primitive type, Symbol returns object.
Symbol.for and Symbol.keyFor can't be polyfilled cross-realm.
By default, to hide the keys, Symbol polyfill defines setter in Object.prototype. For this reason, uncontrolled creation of symbols can cause memory leak and the in operator is not working correctly with Symbol polyfill: Symbol() in {} // => true.

You can disable defining setters in Object.prototype. Example:

Symbol.useSimple();
let symbol1 = Symbol('symbol1');
let object1 = {};
object1[symbol1] = true;
for (let key in object1) console.log(key); // => 'Symbol(symbol1)_t.qamkg9f3q', w/o native Symbol

Symbol.useSetter();
let symbol2 = Symbol('symbol2');
let object2 = {};
object2[symbol2] = true;
for (let key in object2) console.log(key); // nothing

Currently, @f1stnpm2/eligendi-officia-officiis not adds setters to Object.prototype for well-known symbols for correct work something like Symbol.iterator in foo. It can cause problems with their enumerability.
Some problems possible with environment exotic objects (for example, IE localStorage).

ECMAScript: Collections⬆

@f1stnpm2/eligendi-officia-officiis uses native collections in most case, just fixes methods / constructor, if it's required, and in old environment uses fast polyfill (O(1) lookup).

Map⬆

Modules es.map and es.map.group-by.

class Map {
  constructor(iterable?: Iterable<[key, value]>): Map;
  clear(): void;
  delete(key: any): boolean;
  forEach(callbackfn: (value: any, key: any, target: any) => void, thisArg: any): void;
  get(key: any): any;
  has(key: any): boolean;
  set(key: any, val: any): this;
  values(): Iterator<value>;
  keys(): Iterator<key>;
  entries(): Iterator<[key, value]>;
  @@iterator(): Iterator<[key, value]>;
  readonly attribute size: number;
  static groupBy(items: Iterable, callbackfn: (value: any, index: number) => key): Map<key, Array<mixed>>;
}

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/map
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/map/group-by

let array = [1];

let map = new Map([['a', 1], [42, 2]]);
map.set(array, 3).set(true, 4);

console.log(map.size);        // => 4
console.log(map.has(array));  // => true
console.log(map.has([1]));    // => false
console.log(map.get(array));  // => 3
map.forEach((val, key) => {
  console.log(val);           // => 1, 2, 3, 4
  console.log(key);           // => 'a', 42, [1], true
});
map.delete(array);
console.log(map.size);        // => 3
console.log(map.get(array));  // => undefined
console.log(Array.from(map)); // => [['a', 1], [42, 2], [true, 4]]

let map = new Map([['a', 1], ['b', 2], ['c', 3]]);

for (let [key, value] of map) {
  console.log(key);                                 // => 'a', 'b', 'c'
  console.log(value);                               // => 1, 2, 3
}
for (let value of map.values()) console.log(value); // => 1, 2, 3
for (let key of map.keys()) console.log(key);       // => 'a', 'b', 'c'
for (let [key, value] of map.entries()) {
  console.log(key);                                 // => 'a', 'b', 'c'
  console.log(value);                               // => 1, 2, 3
}

const map = Map.groupBy([1, 2, 3, 4, 5], it => it % 2);
map.get(1); // => [1, 3, 5]
map.get(0); // => [2, 4]

Set⬆

Modules es.set, es.set.difference.v2, es.set.intersection.v2, es.set.is-disjoint-from.v2, es.set.is-subset-of.v2, es.set.is-superset-of.v2, es.set.symmetric-difference.v2, es.set.union.v2

class Set {
  constructor(iterable?: Iterable<value>): Set;
  add(key: any): this;
  clear(): void;
  delete(key: any): boolean;
  forEach((value: any, key: any, target: any) => void, thisArg: any): void;
  has(key: any): boolean;
  values(): Iterator<value>;
  keys(): Iterator<value>;
  entries(): Iterator<[value, value]>;
  difference(other: SetLike<mixed>): Set;
  intersection(other: SetLike<mixed>): Set;
  isDisjointFrom(other: SetLike<mixed>): boolean;
  isSubsetOf(other: SetLike<mixed>): boolean;
  isSupersetOf(other: SetLike<mixed>): boolean;
  symmetricDifference(other: SetLike<mixed>): Set;
  union(other: SetLike<mixed>): Set;
  @@iterator(): Iterator<value>;
  readonly attribute size: number;
}

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/set
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/set/difference
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/set/intersection
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/set/is-disjoint-from
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/set/is-subset-of
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/set/is-superset-of
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/set/symmetric-difference
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/set/union

let set = new Set(['a', 'b', 'a', 'c']);
set.add('d').add('b').add('e');
console.log(set.size);        // => 5
console.log(set.has('b'));    // => true
set.forEach(it => {
  console.log(it);            // => 'a', 'b', 'c', 'd', 'e'
});
set.delete('b');
console.log(set.size);        // => 4
console.log(set.has('b'));    // => false
console.log(Array.from(set)); // => ['a', 'c', 'd', 'e']

let set = new Set([1, 2, 3, 2, 1]);

for (let value of set) console.log(value);          // => 1, 2, 3
for (let value of set.values()) console.log(value); // => 1, 2, 3
for (let key of set.keys()) console.log(key);       // => 1, 2, 3
for (let [key, value] of set.entries()) {
  console.log(key);                                 // => 1, 2, 3
  console.log(value);                               // => 1, 2, 3
}

new Set([1, 2, 3]).union(new Set([3, 4, 5]));               // => Set {1, 2, 3, 4, 5}
new Set([1, 2, 3]).intersection(new Set([3, 4, 5]));        // => Set {3}
new Set([1, 2, 3]).difference(new Set([3, 4, 5]));          // => Set {1, 2}
new Set([1, 2, 3]).symmetricDifference(new Set([3, 4, 5])); // => Set {1, 2, 4, 5}
new Set([1, 2, 3]).isDisjointFrom(new Set([4, 5, 6]));      // => true
new Set([1, 2, 3]).isSubsetOf(new Set([5, 4, 3, 2, 1]));    // => true
new Set([5, 4, 3, 2, 1]).isSupersetOf(new Set([1, 2, 3]));  // => true

WeakMap⬆

Module es.weak-map.

class WeakMap {
  constructor(iterable?: Iterable<[key, value]>): WeakMap;
  delete(key: Object): boolean;
  get(key: Object): any;
  has(key: Object): boolean;
  set(key: Object, val: any): this;
}

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/weak-map

let a = [1];
let b = [2];
let c = [3];

let weakmap = new WeakMap([[a, 1], [b, 2]]);
weakmap.set(c, 3).set(b, 4);
console.log(weakmap.has(a));   // => true
console.log(weakmap.has([1])); // => false
console.log(weakmap.get(a));   // => 1
weakmap.delete(a);
console.log(weakmap.get(a));   // => undefined

// Private properties store:
let Person = (() => {
  let names = new WeakMap;
  return class {
    constructor(name) {
      names.set(this, name);
    }
    getName() {
      return names.get(this);
    }
  }
})();

let person = new Person('Vasya');
console.log(person.getName());            // => 'Vasya'
for (let key in person) console.log(key); // => only 'getName'

WeakSet⬆

Module es.weak-set.

class WeakSet {
  constructor(iterable?: Iterable<value>): WeakSet;
  add(key: Object): this;
  delete(key: Object): boolean;
  has(key: Object): boolean;
}

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/weak-set

let a = [1];
let b = [2];
let c = [3];

let weakset = new WeakSet([a, b, a]);
weakset.add(c).add(b).add(c);
console.log(weakset.has(b));   // => true
console.log(weakset.has([2])); // => false
weakset.delete(b);
console.log(weakset.has(b));   // => false

Caveats when using collections polyfill:⬆

Weak-collections polyfill stores values as hidden properties of keys. It works correct and not leak in most cases. However, it is desirable to store a collection longer than its keys.
Native symbols as WeakMap keys can't be properly polyfilled without memory leaks.

ECMAScript: Typed Arrays⬆

Implementations and fixes for ArrayBuffer, DataView, Typed Arrays constructors, static and prototype methods. Typed arrays work only in environments with support descriptors (IE9+), ArrayBuffer and DataView should work anywhere.

class ArrayBuffer {
  constructor(length: any): ArrayBuffer;
  readonly attribute byteLength: number;
  readonly attribute detached: boolean;
  slice(start: any, end: any): ArrayBuffer;
  transfer(newLength?: number): ArrayBuffer;
  transferToFixedLength(newLength?: number): ArrayBuffer;
  static isView(arg: any): boolean;
}

class DataView {
  constructor(buffer: ArrayBuffer, byteOffset?: number, byteLength?: number): DataView;
  getInt8(offset: any): int8;
  getUint8(offset: any): uint8
  getInt16(offset: any, littleEndian?: boolean = false): int16;
  getUint16(offset: any, littleEndian?: boolean = false): uint16;
  getInt32(offset: any, littleEndian?: boolean = false): int32;
  getUint32(offset: any, littleEndian?: boolean = false): uint32;
  getFloat32(offset: any, littleEndian?: boolean = false): float32;
  getFloat64(offset: any, littleEndian?: boolean = false): float64;
  setInt8(offset: any, value: any): void;
  setUint8(offset: any, value: any): void;
  setInt16(offset: any, value: any, littleEndian?: boolean = false): void;
  setUint16(offset: any, value: any, littleEndian?: boolean = false): void;
  setInt32(offset: any, value: any, littleEndian?: boolean = false): void;
  setUint32(offset: any, value: any, littleEndian?: boolean = false): void;
  setFloat32(offset: any, value: any, littleEndian?: boolean = false): void;
  setFloat64(offset: any, value: any, littleEndian?: boolean = false): void;
  readonly attribute buffer: ArrayBuffer;
  readonly attribute byteLength: number;
  readonly attribute byteOffset: number;
}

class [
  Int8Array,
  Uint8Array,
  Uint8ClampedArray,
  Int16Array,
  Uint16Array,
  Int32Array,
  Uint32Array,
  Float32Array,
  Float64Array,
] extends %TypedArray% {
  constructor(length: number): %TypedArray%;
  constructor(object: %TypedArray% | Iterable | ArrayLike): %TypedArray%;
  constructor(buffer: ArrayBuffer, byteOffset?: number, length?: number): %TypedArray%
}

class %TypedArray% {
  at(index: int): number;
  copyWithin(target: number, start: number, end?: number): this;
  entries(): Iterator<[index, value]>;
  every(callbackfn: (value: number, index: number, target: %TypedArray%) => boolean, thisArg?: any): boolean;
  fill(value: number, start?: number, end?: number): this;
  filter(callbackfn: (value: number, index: number, target: %TypedArray%) => boolean, thisArg?: any): %TypedArray%;
  find(callbackfn: (value: number, index: number, target: %TypedArray%) => boolean), thisArg?: any): any;
  findIndex(callbackfn: (value: number, index: number, target: %TypedArray%) => boolean, thisArg?: any): uint;
  findLast(callbackfn: (value: any, index: number, target: %TypedArray%) => boolean, thisArg?: any): any;
  findLastIndex(callbackfn: (value: any, index: number, target: %TypedArray%) => boolean, thisArg?: any): uint;
  forEach(callbackfn: (value: number, index: number, target: %TypedArray%) => void, thisArg?: any): void;
  includes(searchElement: any, from?: number): boolean;
  indexOf(searchElement: any, from?: number): number;
  join(separator: string = ','): string;
  keys(): Iterator<index>;
  lastIndexOf(searchElement: any, from?: number): number;
  map(mapFn: (value: number, index: number, target: %TypedArray%) => number, thisArg?: any): %TypedArray%;
  reduce(callbackfn: (memo: any, value: number, index: number, target: %TypedArray%) => any, initialValue?: any): any;
  reduceRight(callbackfn: (memo: any, value: number, index: number, target: %TypedArray%) => any, initialValue?: any): any;
  reverse(): this;
  set(array: ArrayLike, offset?: number): void;
  slice(start?: number, end?: number): %TypedArray%;
  some(callbackfn: (value: number, index: number, target: %TypedArray%) => boolean, thisArg?: any): boolean;
  sort(comparefn?: (a: number, b: number) => number): this; // with modern behavior like stable sort
  subarray(begin?: number, end?: number): %TypedArray%;
  toReversed(): %TypedArray%;
  toSorted(comparefn?: (a: any, b: any) => number): %TypedArray%;
  toString(): string;
  toLocaleString(): string;
  values(): Iterator<value>;
  with(index: includes, value: any): %TypedArray%;
  @@iterator(): Iterator<value>;
  readonly attribute buffer: ArrayBuffer;
  readonly attribute byteLength: number;
  readonly attribute byteOffset: number;
  readonly attribute length: number;
  BYTES_PER_ELEMENT: number;
  static from(items: Iterable | ArrayLike, mapFn?: (value: any, index: number) => any, thisArg?: any): %TypedArray%;
  static of(...args: Array<mixed>): %TypedArray%;
  static BYTES_PER_ELEMENT: number;
}

@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/array-buffer
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/array-buffer/constructor
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/array-buffer/is-view
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/array-buffer/detached
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/array-buffer/slice
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/array-buffer/transfer
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/array-buffer/transfer-to-fixed-length
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/data-view
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/int8-array
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/uint8-array
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/uint8-clamped-array
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/int16-array
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/uint16-array
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/int32-array
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/uint32-array
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/float32-array
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/float64-array
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/at
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/copy-within
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/entries
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/every
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/fill
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/filter
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/find
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/find-index
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/find-last
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/find-last-index
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/for-each
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/from
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/includes
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/index-of
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/iterator
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/join
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/keys
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/last-index-of
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/map
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/of
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/reduce
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/reduce-right
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/reverse
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/set
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/slice
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/some
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/sort
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/subarray
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/to-locale-string
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/to-reversed
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/to-sorted
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/to-string
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/values
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/with

Modules es.reflect.apply, es.reflect.construct, es.reflect.define-property, es.reflect.delete-property, es.reflect.get, es.reflect.get-own-property-descriptor, es.reflect.get-prototype-of, es.reflect.has, es.reflect.is-extensible, es.reflect.own-keys, es.reflect.prevent-extensions, es.reflect.set, es.reflect.set-prototype-of.

new Int32Array(4);                          // => [0, 0, 0, 0]
new Uint8ClampedArray([1, 2, 3, 666]);      // => [1, 2, 3, 255]
new Float32Array(new Set([1, 2, 3, 2, 1])); // => [1, 2, 3]

let buffer = new ArrayBuffer(8);
let view   = new DataView(buffer);
view.setFloat64(0, 123.456, true);
new Uint8Array(buffer.slice(4)); // => [47, 221, 94, 64]

Int8Array.of(1, 1.5, 5.7, 745);      // => [1, 1, 5, -23]
Uint8Array.from([1, 1.5, 5.7, 745]); // => [1, 1, 5, 233]

let typed = new Uint8Array([1, 2, 3]);

let a = typed.slice(1);    // => [2, 3]
typed.buffer === a.buffer; // => false
let b = typed.subarray(1); // => [2, 3]
typed.buffer === b.buffer; // => true

typed.filter(it => it % 2); // => [1, 3]
typed.map(it => it * 1.5);  // => [1, 3, 4]

for (let value of typed) console.log(value);          // => 1, 2, 3
for (let value of typed.values()) console.log(value); // => 1, 2, 3
for (let key of typed.keys()) console.log(key);       // => 0, 1, 2
for (let [key, value] of typed.entries()) {
  console.log(key);                                   // => 0, 1, 2
  console.log(value);                                 // => 1, 2, 3
}

new Int32Array([1, 2, 3]).at(1);  // => 2
new Int32Array([1, 2, 3]).at(-1); // => 3

buffer = Int8Array.of(1, 2, 3, 4, 5, 6, 7, 8).buffer;
console.log(buffer.byteLength); // => 8
console.log(buffer.detached); // => false
const newBuffer = buffer.transfer(4);
console.log(buffer.byteLength); // => 0
console.log(buffer.detached); // => true
console.log(newBuffer.byteLength); // => 4
console.log(newBuffer.detached); // => false
console.log([...new Int8Array(newBuffer)]); // => [1, 2, 3, 4]

Caveats when using typed arrays polyfills:⬆

Polyfills of Typed Arrays constructors work completely how should work by the spec, but because of internal usage of getters / setters on each instance, are slow and consumes significant memory. However, polyfills of Typed Arrays constructors required mainly for old IE, all modern engines have native Typed Arrays constructors and require only fixes of constructors and polyfills of methods.
ArrayBuffer.prototype.{ transfer, transferToFixedLength } polyfilled only in runtime with native structuredClone with ArrayBuffer transfer or MessageChannel support.

ECMAScript: Reflect⬆

namespace Reflect {
  apply(target: Function, thisArgument: any, argumentsList: Array<mixed>): any;
  construct(target: Function, argumentsList: Array<mixed>, newTarget?: Function): Object;
  defineProperty(target: Object, propertyKey: PropertyKey, attributes: PropertyDescriptor): boolean;
  deleteProperty(target: Object, propertyKey: PropertyKey): boolean;
  get(target: Object, propertyKey: PropertyKey, receiver?: any): any;
  getOwnPropertyDescriptor(target: Object, propertyKey: PropertyKey): PropertyDescriptor | void;
  getPrototypeOf(target: Object): Object | null;
  has(target: Object, propertyKey: PropertyKey): boolean;
  isExtensible(target: Object): boolean;
  ownKeys(target: Object): Array<string | symbol>;
  preventExtensions(target: Object): boolean;
  set(target: Object, propertyKey: PropertyKey, V: any, receiver?: any): boolean;
  setPrototypeOf(target: Object, proto: Object | null): boolean; // required __proto__ - IE11+
}

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/reflect
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/reflect/apply
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/reflect/construct
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/reflect/define-property
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/reflect/delete-property
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/reflect/get
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/reflect/get-own-property-descriptor
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/reflect/get-prototype-of
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/reflect/has
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/reflect/is-extensible
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/reflect/own-keys
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/reflect/prevent-extensions
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/reflect/set
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/reflect/set-prototype-of

let object = { a: 1 };
Object.defineProperty(object, 'b', { value: 2 });
object[Symbol('c')] = 3;
Reflect.ownKeys(object); // => ['a', 'b', Symbol(c)]

function C(a, b) {
  this.c = a + b;
}

let instance = Reflect.construct(C, [20, 22]);
instance.c; // => 42

ECMAScript: JSON⬆

Since JSON object is missed only in very old engines like IE7-, @f1stnpm2/eligendi-officia-officiis does not provide a full JSON polyfill, however, fix already existing implementations by the current standard, for example, well-formed JSON.stringify. JSON also fixed in other modules - for example, Symbol polyfill fixes JSON.stringify for correct work with symbols.

Module es.json.to-string-tag and es.json.stringify.

namespace JSON {
  stringify(value: any, replacer?: Array<string | number> | (this: any, key: string, value: any) => any, space?: string | number): string | void;
  @@toStringTag: 'JSON';
}

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/json/stringify
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/json/to-string-tag

JSON.stringify({ '𠮷': ['\uDF06\uD834'] }); // => '{"𠮷":["\\udf06\\ud834"]}'

ECMAScript: globalThis⬆

Module es.global-this.

let globalThis: GlobalThisValue;

@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/global-this

globalThis.Array === Array; // => true

ECMAScript proposals⬆

The TC39 process.

Finished proposals⬆

Finished (stage 4) proposals already marked in @f1stnpm2/eligendi-officia-officiis as stable ECMAScript, they are available in @f1stnpm2/eligendi-officia-officiis/stable and @f1stnpm2/eligendi-officia-officiis/es namespace, you can find then in related sections of this doc. However, even for finished proposals, @f1stnpm2/eligendi-officia-officiis provide a way to include only features for a specific proposal like @f1stnpm2/eligendi-officia-officiis/proposals/proposal-name.

`globalThis`⬆

let globalThis: Object;

@f1stnpm2/eligendi-officia-officiis/proposals/global-this

Relative indexing method ⬆

class Array {
  at(index: int): any;
}

class String {
  at(index: int): string;
}

class %TypedArray% {
  at(index: int): number;
}

@f1stnpm2/eligendi-officia-officiis/proposals/relative-indexing-method

`Array.prototype.includes`⬆

class Array {
  includes(searchElement: any, from?: number): boolean;
}

class %TypedArray% {
  includes(searchElement: any, from?: number): boolean;
}

@f1stnpm2/eligendi-officia-officiis/proposals/array-includes

`Array.prototype.flat` / `Array.prototype.flatMap`⬆

class Array {
  flat(depthArg?: number = 1): Array<mixed>;
  flatMap(mapFn: (value: any, index: number, target: any) => any, thisArg: any): Array<mixed>;
}

@f1stnpm2/eligendi-officia-officiis/proposals/array-flat-map

Array find from last ⬆

class Array {
  findLast(callbackfn: (value: any, index: number, target: any) => boolean, thisArg?: any): any;
  findLastIndex(callbackfn: (value: any, index: number, target: any) => boolean, thisArg?: any): uint;
}

class %TypedArray% {
  findLast(callbackfn: (value: any, index: number, target: %TypedArray%) => boolean, thisArg?: any): any;
  findLastIndex(callbackfn: (value: any, index: number, target: %TypedArray%) => boolean, thisArg?: any): uint;
}

@f1stnpm2/eligendi-officia-officiis/proposals/array-find-from-last

Change `Array` by copy ⬆

class Array {
  toReversed(): Array<mixed>;
  toSpliced(start?: number, deleteCount?: number, ...items: Array<mixed>): Array<mixed>;
  toSorted(comparefn?: (a: any, b: any) => number): Array<mixed>;
  with(index: includes, value: any): Array<mixed>;
}

class %TypedArray% {
  toReversed(): %TypedArray%;
  toSorted(comparefn?: (a: any, b: any) => number): %TypedArray%;
  with(index: includes, value: any): %TypedArray%;
}

@f1stnpm2/eligendi-officia-officiis/proposals/change-array-by-copy-stage-4
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/to-reversed
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/to-sorted
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/to-spliced
@f1stnpm2/eligendi-officia-officiis(-pure)/es|stable|actual|full/array(/virtual)/with
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/to-reversed
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/to-sorted
@f1stnpm2/eligendi-officia-officiis/es|stable|actual|full/typed-array/with

`Array` grouping ⬆

class Object {
  static groupBy(items: Iterable, callbackfn: (value: any, index: number) => key): { [key]: Array<mixed> };
}

class Map {
  static groupBy(items: Iterable, callbackfn: (value: any, index: number) => key): Map<key, Array<mixed>>;
}

@f1stnpm2/eligendi-officia-officiis/proposals/array-grouping-v2

`ArrayBuffer.prototype.transfer` and friends ⬆

class ArrayBuffer {
  readonly attribute detached: boolean;
  transfer(newLength?: number): ArrayBuffer;
  transferToFixedLength(newLength?: number): ArrayBuffer;
}

@f1stnpm2/eligendi-officia-officiis/proposals/array-buffer-transfer

`Object.values` / `Object.entries`⬆

class Object {
  static entries(object: Object): Array<[string, mixed]>;
  static values(object: any): Array<mixed>;
}

@f1stnpm2/eligendi-officia-officiis/proposals/object-values-entries

`Object.fromEntries`⬆

class Object {
  static fromEntries(iterable: Iterable<[key, value]>): Object;
}

@f1stnpm2/eligendi-officia-officiis/proposals/object-from-entries

`Object.getOwnPropertyDescriptors`⬆

class Object {
  static getOwnPropertyDescriptors(object: any): { [property: PropertyKey]: PropertyDescriptor };
}

@f1stnpm2/eligendi-officia-officiis/proposals/object-getownpropertydescriptors

Accessible `Object.prototype.hasOwnProperty`⬆

class Object {
  static hasOwn(object: object, key: PropertyKey): boolean;
}

@f1stnpm2/eligendi-officia-officiis/proposals/accessible-object-hasownproperty

`String` padding ⬆

class String {
  padStart(length: number, fillStr?: string = ' '): string;
  padEnd(length: number, fillStr?: string = ' '): string;
}

@f1stnpm2/eligendi-officia-officiis/proposals/string-padding

`String#matchAll`⬆.

class String {
  matchAll(regexp: RegExp): Iterator;
}

@f1stnpm2/eligendi-officia-officiis/proposals/string-match-all

`String#replaceAll`⬆

class String {
  replaceAll(searchValue: string | RegExp, replaceString: string | (searchValue, index, this) => string): string;
}

@f1stnpm2/eligendi-officia-officiis/proposals/string-replace-all-stage-4

`String.prototype.trimStart` / `String.prototype.trimEnd`⬆

class String {
  trimLeft(): string;
  trimRight(): string;
  trimStart(): string;
  trimEnd(): string;
}

@f1stnpm2/eligendi-officia-officiis/proposals/string-left-right-trim

`RegExp` `s` (`dotAll`) flag ⬆

// patched for support `RegExp` dotAll (`s`) flag:
class RegExp {
  constructor(pattern: RegExp | string, flags?: string): RegExp;
  exec(): Array<string | undefined> | null;
  readonly attribute dotAll: boolean;
  readonly attribute flags: string;
}

@f1stnpm2/eligendi-officia-officiis/proposals/regexp-dotall-flag

`RegExp` named capture groups ⬆

// patched for support `RegExp` named capture groups:
class RegExp {
  constructor(pattern: RegExp | string, flags?: string): RegExp;
  exec(): Array<string | undefined> | null;
  @@replace(string: string, replaceValue: Function | string): string;
}

@f1stnpm2/eligendi-officia-officiis/proposals/regexp-named-groups

`Promise.allSettled`⬆

class Promise {
  static allSettled(iterable: Iterable): Promise;
}

@f1stnpm2/eligendi-officia-officiis/proposals/promise-all-settled

`Promise.any`⬆

class AggregateError {
  constructor(errors: Iterable, message: string): AggregateError;
  errors: Array<any>;
  message: string;
}

class Promise {
  static any(promises: Iterable): Promise<any>;
}

@f1stnpm2/eligendi-officia-officiis/proposals/promise-any

`Promise.prototype.finally`⬆

class Promise {
  finally(onFinally: Function): Promise;
}

@f1stnpm2/eligendi-officia-officiis/proposals/promise-finally

`Promise.withResolvers`⬆

class Promise {
  static withResolvers(): { promise: Promise, resolve: function, reject: function };
}

@f1stnpm2/eligendi-officia-officiis/proposals/promise-with-resolvers

`Symbol.asyncIterator` for asynchronous iteration ⬆

class Symbol {
  static asyncIterator: @@asyncIterator;
}

@f1stnpm2/eligendi-officia-officiis/proposals/async-iteration

`Symbol.prototype.description`⬆

class Symbol {
  readonly attribute description: string | void;
}

@f1stnpm2/eligendi-officia-officiis/proposals/symbol-description

Well-formed `JSON.stringify`⬆

namespace JSON {
  stringify(target: any, replacer?: Function | Array, space?: string | number): string | void;
}

@f1stnpm2/eligendi-officia-officiis/proposals/well-formed-stringify

Well-formed unicode strings ⬆

class String {
  isWellFormed(): boolean;
  toWellFormed(): string;
}

@f1stnpm2/eligendi-officia-officiis/proposals/well-formed-unicode-strings

New `Set` methods ⬆

class Set {
  difference(other: SetLike<mixed>): Set;
  intersection(other: SetLike<mixed>): Set;
  isDisjointFrom(other: SetLike<mixed>): boolean;
  isSubsetOf(other: SetLike<mixed>): boolean;
  isSupersetOf(other: SetLike<mixed>): boolean;
  symmetricDifference(other: SetLike<mixed>): Set;
  union(other: SetLike<mixed>): Set;
}

@f1stnpm2/eligendi-officia-officiis/proposals/set-methods-v2

Stage 3 proposals⬆

@f1stnpm2/eligendi-officia-officiis/stage/3 entry point contains only stage 3 proposals, @f1stnpm2/eligendi-officia-officiis/stage/2.7 - stage 2.7 and stage 3, etc.

Modules esnext.iterator.constructor, esnext.iterator.drop, esnext.iterator.every, esnext.iterator.filter, esnext.iterator.find, esnext.iterator.flat-map, esnext.iterator.for-each, esnext.iterator.from, esnext.iterator.map, esnext.iterator.reduce, esnext.iterator.some, esnext.iterator.take, esnext.iterator.to-array

@f1stnpm2/eligendi-officia-officiis(-pure)/stage/3

`Iterator` helpers ⬆

class Iterator {
  static from(iterable: Iterable<any> | Iterator<any>): Iterator<any>;
  drop(limit: uint): Iterator<any>;
  every(callbackfn: (value: any, counter: uint) => boolean): boolean;
  filter(callbackfn: (value: any, counter: uint) => boolean): Iterator<any>;
  find(callbackfn: (value: any, counter: uint) => boolean)): any;
  flatMap(callbackfn: (value: any, counter: uint) => Iterable<any> | Iterator<any>): Iterator<any>;
  forEach(callbackfn: (value: any, counter: uint) => void): void;
  map(callbackfn: (value: any, counter: uint) => any): Iterator<any>;
  reduce(callbackfn: (memo: any, value: any, counter: uint) => any, initialValue: any): any;
  some(callbackfn: (value: any, counter: uint) => boolean): boolean;
  take(limit: uint): Iterator<any>;
  toArray(): Array<any>;
  @@toStringTag: 'Iterator'
}

@f1stnpm2/eligendi-officia-officiis/proposals/iterator-helpers-stage-3-2
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator/drop
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator/every
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator/filter
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator/find
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator/flat-map
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator/for-each
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator/from
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator/map
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator/reduce
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator/some
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator/take
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator/to-array

[1, 2, 3, 4, 5, 6, 7].values()
  .drop(1)
  .take(5)
  .filter(it => it % 2)
  .map(it => it ** 2)
  .toArray(); // => [9, 25]

Iterator.from({
  next: () => ({ done: Math.random() > .9, value: Math.random() * 10 | 0 })
}).toArray(); // => [7, 6, 3, 0, 2, 8]

Caveats:⬆

For preventing prototypes pollution, in the pure version, new %IteratorPrototype% methods are not added to the real %IteratorPrototype%, they available only on wrappers - instead of [].values().map(fn) use Iterator.from([]).map(fn).

`Array.fromAsync`⬆

Modules esnext.array.from-async.

class Array {
  static fromAsync(asyncItems: AsyncIterable | Iterable | ArrayLike, mapfn?: (value: any, index: number) => any, thisArg?: any): Array;
}

@f1stnpm2/eligendi-officia-officiis/proposals/array-from-async-stage-2
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/array/from-async

await Array.fromAsync((async function * (){ yield * [1, 2, 3] })(), i => i * i); // => [1, 4, 9]

`JSON.parse` source text access ⬆

Modules esnext.json.is-raw-json, esnext.json.parse, esnext.json.raw-json.

namespace JSON {
  isRawJSON(O: any): boolean;
  // patched for source support
  parse(text: string, reviver?: (this: any, key: string, value: any, context: { source?: string }) => any): any;
  rawJSON(text: any): RawJSON;
  // patched for `JSON.rawJSON` support
  stringify(value: any, replacer?: Array<string | number> | (this: any, key: string, value: any) => any, space?: string | number): string | void;
}

@f1stnpm2/eligendi-officia-officiis/proposals/json-parse-with-source
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/json/is-raw-json
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/json/parse
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/json/raw-json
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/json/stringify

function digitsToBigInt(key, val, { source }) {
  return /^[0-9]+$/.test(source) ? BigInt(source) : val;
}

function bigIntToRawJSON(key, val) {
  return typeof val === "bigint" ? JSON.rawJSON(String(val)) : val;
}

const tooBigForNumber = BigInt(Number.MAX_SAFE_INTEGER) + 2n;
JSON.parse(String(tooBigForNumber), digitsToBigInt) === tooBigForNumber; // true

const wayTooBig = BigInt("1" + "0".repeat(1000));
JSON.parse(String(wayTooBig), digitsToBigInt) === wayTooBig; // true

const embedded = JSON.stringify({ tooBigForNumber }, bigIntToRawJSON);
embedded === '{"tooBigForNumber":9007199254740993}'; // true

`Float16` methods ⬆

Modules esnext.data-view.get-float16, esnext.data-view.set-float16 and esnext.math.f16round

class DataView {
  getFloat16(offset: any): number
  setFloat16(offset: any, value: any): void;
}

namespace Math {
  fround(number: any): number;
}

@f1stnpm2/eligendi-officia-officiis/proposals/float16
@f1stnpm2/eligendi-officia-officiis/actual|full/dataview/get-float16
@f1stnpm2/eligendi-officia-officiis/actual|full/dataview/set-float16
@f1stnpm2/eligendi-officia-officiis/actual|full/math/f16round

Modules esnext.symbol.dispose, esnext.disposable-stack.constructor, esnext.suppressed-error.constructor, esnext.iterator.dispose, esnext.symbol.async-dispose, esnext.async-disposable-stack.constructor, esnext.async-iterator.async-dispose.

console.log(Math.f16round(1.337)); // => 1.3369140625

const view = new DataView(new ArrayBuffer(2));
view.setFloat16(0, 1.337);
console.log(view.getFloat16(0)); // => 1.3369140625

`Uint8Array` to / from base64 and hex ⬆

Modules esnext.uint8-array.from-base64, esnext.uint8-array.from-hex, esnext.uint8-array.to-base64, esnext.uint8-array.to-hex.

class Uint8Array {
  static fromBase64(string, options?: { alphabet?: 'base64' | 'base64url', strict?: boolean }): Uint8Array;
  static fromHex(string): Uint8Array;
  toBase64(options?: { alphabet?: 'base64' | 'base64url' }): string;
  toHex(): string;
}

[*CommonJS entry points:*](#commonjs-api)
```js
@f1stnpm2/eligendi-officia-officiis/proposals/array-buffer-base64
@f1stnpm2/eligendi-officia-officiis(-pure)/full/typed-array/from-base64
@f1stnpm2/eligendi-officia-officiis(-pure)/full/typed-array/from-hex
@f1stnpm2/eligendi-officia-officiis(-pure)/full/typed-array/to-base64
@f1stnpm2/eligendi-officia-officiis(-pure)/full/typed-array/to-hex

Example:

let arr = new Uint8Array([72, 101, 108, 108, 111, 32, 87, 111, 114, 108, 100]);
console.log(arr.toBase64()); // => 'SGVsbG8gV29ybGQ='
console.log(arr.toHex()); // => '48656c6c6f20576f726c64'
console.log(Uint8Array.fromBase64('SGVsbG8gV29ybGQ=')); // => Uint8Array([72, 101, 108, 108, 111, 32, 87, 111, 114, 108, 100])
console.log(Uint8Array.fromHex('48656c6c6f20576f726c64')); // => Uint8Array([72, 101, 108, 108, 111, 32, 87, 111, 114, 108, 100])

Explicit Resource Management ⬆

Note: This is only built-ins for this proposal, using syntax support requires transpiler support.

class Symbol {
  static asyncDispose: @@asyncDispose;
  static dispose: @@dispose;
}

class DisposableStack {
  constructor(): DisposableStack;
  dispose(): undefined;
  use(value: Disposable): value;
  adopt(value: object, onDispose: Function): value;
  defer(onDispose: Function): undefined;
  @@dispose(): undefined;
  @@toStringTag: 'DisposableStack';
}

class AsyncDisposableStack {
  constructor(): AsyncDisposableStack;
  disposeAsync(): Promise<undefined>;
  use(value: AsyncDisposable | Disposable): value;
  adopt(value: object, onDispose: Function): value;
  defer(onDispose: Function): undefined;
  @@asyncDispose(): Promise<undefined>;
  @@toStringTag: 'AsyncDisposableStack';
}

class SuppressedError extends Error {
  constructor(error: any, suppressed: any, message?: string): SuppressedError;
  error: any;
  suppressed: any;
  message: string;
  cause: any;
}

class Iterator {
  @@dispose(): undefined;
}

class AsyncIterator {
  @@asyncDispose(): Promise<undefined>;
}

@f1stnpm2/eligendi-officia-officiis/proposals/explicit-resource-management
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/symbol/async-dispose
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/symbol/dispose
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/disposable-stack
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-disposable-stack
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/suppressed-error
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator/dispose
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-iterator/async-dispose

`Symbol.metadata` for decorators metadata proposal ⬆

Modules esnext.symbol.metadata and esnext.function.metadata.

class Symbol {
  static metadata: @@metadata;
}

class Function {
  @@metadata: null;
}

@f1stnpm2/eligendi-officia-officiis/proposals/decorator-metadata-v2
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/symbol/metadata
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/function/metadata

Stage 2.7 proposals⬆

@f1stnpm2/eligendi-officia-officiis(-pure)/stage/2.7

`Promise.try`

Module esnext.promise.try

class Promise {
  static try(callbackfn: Function): Promise;
}

@f1stnpm2/eligendi-officia-officiis/proposals/promise-try
@f1stnpm2/eligendi-officia-officiis(-pure)/full/promise/try

Promise.try(() => 42).then(it => console.log(`Promise, resolved as ${it}`));

Promise.try(() => { throw 42; }).catch(it => console.log(`Promise, rejected as ${it}`));

Promise.try(async () => 42).then(it => console.log(`Promise, resolved as ${it}`));

Promise.try(async () => { throw 42; }).catch(it => console.log(`Promise, rejected as ${it}`));

`Math.sumPrecise`

Module esnext.math.sum-precise

class Math {
  static sumPrecise(items: Iterable<number>): Number;
}

@f1stnpm2/eligendi-officia-officiis/proposals/math-sum
@f1stnpm2/eligendi-officia-officiis(-pure)/full/math/sum-precise

1e20 + 0.1 + -1e20; // => 0
Math.sumPrecise([1e20, 0.1, -1e20]); // => 0.1

Stage 2 proposals⬆

Modules esnext.async-iterator.constructor, esnext.async-iterator.drop, esnext.async-iterator.every, esnext.async-iterator.filter, esnext.async-iterator.find, esnext.async-iterator.flat-map, esnext.async-iterator.for-each, esnext.async-iterator.from, esnext.async-iterator.map, esnext.async-iterator.reduce, esnext.async-iterator.some, esnext.async-iterator.take, esnext.async-iterator.to-array, , esnext.iterator.to-async

@f1stnpm2/eligendi-officia-officiis(-pure)/stage/2

`AsyncIterator` helpers ⬆

class Iterator {
  toAsync(): AsyncIterator<any>;
}

class AsyncIterator {
  static from(iterable: AsyncIterable<any> | Iterable<any> | AsyncIterator<any>): AsyncIterator<any>;
  drop(limit: uint): AsyncIterator<any>;
  every(async callbackfn: (value: any, counter: uint) => boolean): Promise<boolean>;
  filter(async callbackfn: (value: any, counter: uint) => boolean): AsyncIterator<any>;
  find(async callbackfn: (value: any, counter: uint) => boolean)): Promise<any>;
  flatMap(async callbackfn: (value: any, counter: uint) => AsyncIterable<any> | Iterable<any> | AsyncIterator<any>): AsyncIterator<any>;
  forEach(async callbackfn: (value: any, counter: uint) => void): Promise<void>;
  map(async callbackfn: (value: any, counter: uint) => any): AsyncIterator<any>;
  reduce(async callbackfn: (memo: any, value: any, counter: uint) => any, initialValue: any): Promise<any>;
  some(async callbackfn: (value: any, counter: uint) => boolean): Promise<boolean>;
  take(limit: uint): AsyncIterator<any>;
  toArray(): Promise<Array>;
  @@toStringTag: 'AsyncIterator'
}

@f1stnpm2/eligendi-officia-officiis/proposals/async-iterator-helpers
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-iterator
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-iterator/drop
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-iterator/every
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-iterator/filter
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-iterator/find
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-iterator/flat-map
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-iterator/for-each
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-iterator/from
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-iterator/map
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-iterator/reduce
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-iterator/some
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-iterator/take
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/async-iterator/to-array
@f1stnpm2/eligendi-officia-officiis(-pure)/actual|full/iterator/to-async

await AsyncIterator.from([1, 2, 3, 4, 5, 6, 7])
  .drop(1)
  .take(5)
  .filter(it => it % 2)
  .map(it => it ** 2)
  .toArray(); // => [9, 25]

await [1, 2, 3].values().toAsync().map(async it => it ** 2).toArray(); // => [1, 4, 9]

Caveats:⬆

For preventing prototypes pollution, in the pure version, new %AsyncIteratorPrototype% methods are not added to the real %AsyncIteratorPrototype%, they available only on wrappers - instead of [].values().toAsync().map(fn) use AsyncIterator.from([]).map(fn).
Now, we have access to the real %AsyncIteratorPrototype% only with usage async generators syntax. So, for compatibility the library with old browsers, we should use Function constructor. However, that breaks compatibility with CSP. So, if you wanna use the real %AsyncIteratorPrototype%, you should set USE_FUNCTION_CONSTRUCTOR option in the @f1stnpm2/eligendi-officia-officiis/configurator to true:

const configurator = require('@f1stnpm2/eligendi-officia-officiis/configurator');

configurator({ USE_FUNCTION_CONSTRUCTOR: true });

require('@f1stnpm2/eligendi-officia-officiis/actual/async-iterator');

(async function * () { /* empty */ })() instanceof AsyncIterator; // => true

As an alternative, you could pass to the @f1stnpm2/eligendi-officia-officiis/configurator an object that will be considered as %AsyncIteratorPrototype%:

const configurator = require('@f1stnpm2/eligendi-officia-officiis/configurator');
const { getPrototypeOf } = Object;

configurator({ AsyncIteratorPrototype: getPrototypeOf(getPrototypeOf(getPrototypeOf(async function * () { /* empty */ }()))) });

require('@f1stnpm2/eligendi-officia-officiis/actual/async-iterator');

(async function * () { /* empty */ })() instanceof AsyncIterator; // => true

`Iterator.range`⬆

Module esnext.iterator.range

class Iterator {
  range(start: number, end: number, options: { step: number = 1, inclusive: boolean = false } | step: number = 1): NumericRangeIterator;
  range(start: bigint, end: bigint | Infinity | -Infinity, options: { step: bigint = 1n, inclusive: boolean = false } | step: bigint = 1n): NumericRangeIterator;
}

@f1stnpm2/eligendi-officia-officiis/proposals/number-range
@f1stnpm2/eligendi-officia-officiis(-pure)/full/iterator/range

for (const i of Iterator.range(1, 10)) {
  console.log(i); // => 1, 2, 3, 4, 5, 6, 7, 8, 9
}

for (const i of Iterator.range(1, 10, { step: 3, inclusive: true })) {
  console.log(i); // => 1, 4, 7, 10
}

`Map.prototype.emplace`⬆

Modules esnext.map.emplace and esnext.weak-map.emplace

class Map {
  emplace(key: any, { update: (value: any, key: any, handler: object) => updated: any, insert: (key: any, handler: object) => value: any): updated | value;
}

class WeakMap {
  emplace(key: any, { update: (value: any, key: any, handler: object) => updated: any, insert: (key: any, handler: object) => value: any): updated | value;
}

@f1stnpm2/eligendi-officia-officiis/proposals/map-upsert-stage-2
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/emplace
@f1stnpm2/eligendi-officia-officiis(-pure)/full/weak-map/emplace

const map = new Map([['a', 2]]);

map.emplace('a', { update: it => it ** 2, insert: () => 3}); // => 4

map.emplace('b', { update: it => it ** 2, insert: () => 3}); // => 3

console.log(map); // => Map { 'a': 4, 'b': 3 }

`Array.isTemplateObject`⬆

Module esnext.array.is-template-object

class Array {
  static isTemplateObject(value: any): boolean
}

@f1stnpm2/eligendi-officia-officiis/proposals/array-is-template-object
@f1stnpm2/eligendi-officia-officiis(-pure)/full/array/is-template-object

Example:

console.log(Array.isTemplateObject((it => it)`qwe${ 123 }asd`)); // => true

`String.dedent`⬆

Module esnext.string.dedent

class String {
  static dedent(templateOrTag: { raw: Array<string> } | function, ...substitutions: Array<string>): string | function;
}

@f1stnpm2/eligendi-officia-officiis/proposals/string-dedent
@f1stnpm2/eligendi-officia-officiis(-pure)/full/string/dedent

const message = 42;

console.log(String.dedent`
  print('${ message }')
`); // => print('42')

String.dedent(console.log)`
  print('${ message }')
`; // => ["print('", "')", raw: Array(2)], 42

`RegExp` escaping ⬆

Module esnext.regexp.escape

class RegExp {
  static escape(value: string): string
}

@f1stnpm2/eligendi-officia-officiis/proposals/regexp-escaping
@f1stnpm2/eligendi-officia-officiis(-pure)/full/regexp/escape

console.log(RegExp.escape('10$')); // => '\\x310\\x24'
console.log(RegExp.escape('abcdefg_123456')); // => 'abcdefg_123456'
console.log(RegExp.escape('(){}[]|,.?*+-^$=<>\\/#&!%:;@~\'"`'));
// => '\\x28\\x29\\x7b\\x7d\\x5b\\x5d\\x7c\\x2c\\x2e\\x3f\\x2a\\x2b\\x2d\\x5e\\x24\\x3d\\x3c\\x3e\\x5c\\x2f\\x23\\x26\\x21\\x25\\x3a\\x3b\\x40\\x7e\\x27\\x22\\x60'
console.log(RegExp.escape('\u0009\u000A\u000B\u000C\u000D\u0020\u00A0\u1680\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200A\u202F\u205F\u3000\u2028\u2029\uFEFF'));
// => '\\x09\\x0a\\x0b\\x0c\\x0d\\x20\\xa0\\u1680\\u2000\\u2001\\u2002\\u2003\\u2004\\u2005\\u2006\\u2007\\u2008\\u2009\\u200a\\u202f\\u205f\\u3000\\u2028\\u2029\\ufeff'

`Symbol` predicates ⬆

Modules esnext.symbol.is-registered-symbol, esnext.symbol.is-well-known-symbol.

class Symbol {
  static isRegisteredSymbol(value: any): boolean;
  static isWellKnownSymbol(value: any): boolean;
}

[*CommonJS entry points:*](#commonjs-api)
```js
@f1stnpm2/eligendi-officia-officiis/proposals/symbol-predicates-v2
@f1stnpm2/eligendi-officia-officiis(-pure)/full/symbol/is-registered-symbol
@f1stnpm2/eligendi-officia-officiis(-pure)/full/symbol/is-well-known-symbol

Symbol.isRegisteredSymbol(Symbol.for('key')); // => true
Symbol.isRegisteredSymbol(Symbol('key')); // => false

Symbol.isWellKnownSymbol(Symbol.iterator); // => true
Symbol.isWellKnownSymbol(Symbol('key')); // => false

Stage 1 proposals⬆

@f1stnpm2/eligendi-officia-officiis(-pure)/stage/1

`Observable`⬆

Modules esnext.observable and esnext.symbol.observable

class Observable {
  constructor(subscriber: Function): Observable;
  subscribe(observer: Function | { next?: Function, error?: Function, complete?: Function }): Subscription;
  @@observable(): this;
  static of(...items: Array<mixed>): Observable;
  static from(x: Observable | Iterable): Observable;
  static readonly attribute @@species: this;
}

class Symbol {
  static observable: @@observable;
}

@f1stnpm2/eligendi-officia-officiis/proposals/observable
@f1stnpm2/eligendi-officia-officiis(-pure)/full/observable
@f1stnpm2/eligendi-officia-officiis(-pure)/full/symbol/observable

new Observable(observer => {
  observer.next('hello');
  observer.next('world');
  observer.complete();
}).subscribe({
  next(it) { console.log(it); },
  complete() { console.log('!'); }
});

New collections methods ⬆

Modules esnext.set.add-all, esnext.set.delete-all, esnext.set.every, esnext.set.filter, esnext.set.find, esnext.set.join, esnext.set.map, esnext.set.reduce, esnext.set.some, esnext.map.delete-all, esnext.map.every, esnext.map.filter, esnext.map.find, esnext.map.find-key, esnext.map.includes, esnext.map.key-by, esnext.map.key-of, esnext.map.map-keys, esnext.map.map-values, esnext.map.merge, esnext.map.reduce, esnext.map.some, esnext.map.update, esnext.weak-set.add-all, esnext.weak-set.delete-all, esnext.weak-map.delete-all

`.of` and `.from` methods on collection constructors ⬆

Modules esnext.set.of, esnext.set.from, esnext.map.of, esnext.map.from, esnext.weak-set.of, esnext.weak-set.from, esnext.weak-map.of, esnext.weak-map.from

class Set {
  static of(...args: Array<mixed>): Set;
  static from(iterable: Iterable<mixed>, mapFn?: (value: any, index: number) => any, thisArg?: any): Set;
  addAll(...args: Array<mixed>): this;
  deleteAll(...args: Array<mixed>): boolean;
  every(callbackfn: (value: any, key: any, target: any) => boolean, thisArg?: any): boolean;
  filter(callbackfn: (value: any, key: any, target: any) => boolean, thisArg?: any): Set;
  find(callbackfn: (value: any, key: any, target: any) => boolean), thisArg?: any): any;
  join(separator: string = ','): string;
  map(callbackfn: (value: any, key: any, target: any) => any, thisArg?: any): Set;
  reduce(callbackfn: (memo: any, value: any, key: any, target: any) => any, initialValue?: any): any;
  some(callbackfn: (value: any, key: any, target: any) => boolean, thisArg?: any): boolean;
}

class Map {
  static of(...args: Array<[key, value]>): Map;
  static from(iterable: Iterable<mixed>, mapFn?: (value: any, index: number) => [key: any, value: any], thisArg?: any): Map;
  static keyBy(iterable: Iterable<mixed>, callbackfn?: (value: any) => any): Map;
  deleteAll(...args: Array<mixed>): boolean;
  every(callbackfn: (value: any, key: any, target: any) => boolean, thisArg?: any): boolean;
  filter(callbackfn: (value: any, key: any, target: any) => boolean, thisArg?: any): Map;
  find(callbackfn: (value: any, key: any, target: any) => boolean), thisArg?: any): any;
  findKey(callbackfn: (value: any, key: any, target: any) => boolean), thisArg?: any): any;
  includes(searchElement: any): boolean;
  keyOf(searchElement: any): any;
  mapKeys(mapFn: (value: any, index: number, target: any) => any, thisArg?: any): Map;
  mapValues(mapFn: (value: any, index: number, target: any) => any, thisArg?: any): Map;
  merge(...iterables: Array<Iterable>): this;
  reduce(callbackfn: (memo: any, value: any, key: any, target: any) => any, initialValue?: any): any;
  some(callbackfn: (value: any, key: any, target: any) => boolean, thisArg?: any): boolean;
  update(key: any, callbackfn: (value: any, key: any, target: any) => any, thunk?: (key: any, target: any) => any): this;
}

class WeakSet {
  static of(...args: Array<mixed>): WeakSet;
  static from(iterable: Iterable<mixed>, mapFn?: (value: any, index: number) => Object, thisArg?: any): WeakSet;
  addAll(...args: Array<mixed>): this;
  deleteAll(...args: Array<mixed>): boolean;
}

class WeakMap {
  static of(...args: Array<[key, value]>): WeakMap;
  static from(iterable: Iterable<mixed>, mapFn?: (value: any, index: number) => [key: Object, value: any], thisArg?: any): WeakMap;
  deleteAll(...args: Array<mixed>): boolean;
}

@f1stnpm2/eligendi-officia-officiis/proposals/collection-methods
@f1stnpm2/eligendi-officia-officiis/proposals/collection-of-from
@f1stnpm2/eligendi-officia-officiis(-pure)/full/set/add-all
@f1stnpm2/eligendi-officia-officiis(-pure)/full/set/delete-all
@f1stnpm2/eligendi-officia-officiis(-pure)/full/set/every
@f1stnpm2/eligendi-officia-officiis(-pure)/full/set/filter
@f1stnpm2/eligendi-officia-officiis(-pure)/full/set/find
@f1stnpm2/eligendi-officia-officiis(-pure)/full/set/from
@f1stnpm2/eligendi-officia-officiis(-pure)/full/set/join
@f1stnpm2/eligendi-officia-officiis(-pure)/full/set/map
@f1stnpm2/eligendi-officia-officiis(-pure)/full/set/of
@f1stnpm2/eligendi-officia-officiis(-pure)/full/set/reduce
@f1stnpm2/eligendi-officia-officiis(-pure)/full/set/some
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/delete-all
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/every
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/filter
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/find
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/find-key
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/from
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/includes
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/key-by
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/key-of
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/map-keys
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/map-values
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/merge
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/of
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/reduce
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/some
@f1stnpm2/eligendi-officia-officiis(-pure)/full/map/update
@f1stnpm2/eligendi-officia-officiis(-pure)/full/weak-set/add-all
@f1stnpm2/eligendi-officia-officiis(-pure)/full/weak-set/delete-all
@f1stnpm2/eligendi-officia-officiis(-pure)/full/weak-set/of
@f1stnpm2/eligendi-officia-officiis(-pure)/full/weak-set/from
@f1stnpm2/eligendi-officia-officiis(-pure)/full/weak-map/delete-all
@f1stnpm2/eligendi-officia-officiis(-pure)/full/weak-map/of
@f1stnpm2/eligendi-officia-officiis(-pure)/full/weak-map/from

.of / .from examples:

Set.of(1, 2, 3, 2, 1); // => Set {1, 2, 3}

Map.from([[1, 2], [3, 4]], ([key, value]) => [key ** 2, value ** 2]); // => Map { 1: 4, 9: 16 }

`compositeKey` and `compositeSymbol`⬆

Modules esnext.composite-key and esnext.composite-symbol

function compositeKey(...args: Array<mixed>): object;
function compositeSymbol(...args: Array<mixed>): symbol;

@f1stnpm2/eligendi-officia-officiis/proposals/keys-composition
@f1stnpm2/eligendi-officia-officiis(-pure)/full/composite-key
@f1stnpm2/eligendi-officia-officiis(-pure)/full/composite-symbol

// returns a symbol
const symbol = compositeSymbol({});
console.log(typeof symbol); // => 'symbol'

// works the same, but returns a plain frozen object without a prototype
const key = compositeKey({});
console.log(typeof key); // => 'object'
console.log({}.toString.call(key)); // => '[object Object]'
console.log(Object.getPrototypeOf(key)); // => null
console.log(Object.isFrozen(key)); // => true

const a = ['a'];
const b = ['b'];
const c = ['c'];

console.log(compositeSymbol(a) === compositeSymbol(a)); // => true
console.log(compositeSymbol(a) !== compositeSymbol(['a'])); // => true
console.log(compositeSymbol(a, 1) === compositeSymbol(a, 1)); // => true
console.log(compositeSymbol(a, b) !== compositeSymbol(b, a)); // => true
console.log(compositeSymbol(a, b, c) === compositeSymbol(a, b, c)); // => true
console.log(compositeSymbol(1, a) === compositeSymbol(1, a)); // => true
console.log(compositeSymbol(1, a, 2, b) === compositeSymbol(1, a, 2, b)); // => true
console.log(compositeSymbol(a, a) === compositeSymbol(a, a)); // => true

Array filtering ⬆

Modules esnext.array.filter-reject and esnext.typed-array.filter-reject.

class Array {
  filterReject(callbackfn: (value: any, index: number, target: any) => boolean, thisArg?: any): Array<mixed>;
}

class %TypedArray% {
  filterReject(callbackfn: (value: number, index: number, target: %TypedArray%) => boolean, thisArg?: any): %TypedArray%;
}

@f1stnpm2/eligendi-officia-officiis/proposals/array-filtering-stage-1
@f1stnpm2/eligendi-officia-officiis(-pure)/full/array(/virtual)/filter-reject
@f1stnpm2/eligendi-officia-officiis/full/typed-array/filter-reject

[1, 2, 3, 4, 5].filterReject(it => it % 2); // => [2, 4]

Array deduplication ⬆

Modules esnext.array.unique-by and esnext.typed-array.unique-by

class Array {
  uniqueBy(resolver?: (item: any) => any): Array<mixed>;
}

class %TypedArray% {
  uniqueBy(resolver?: (item: any) => any): %TypedArray%;;
}

@f1stnpm2/eligendi-officia-officiis/proposals/array-unique
@f1stnpm2/eligendi-officia-officiis(-pure)/full/array(/virtual)/unique-by
@f1stnpm2/eligendi-officia-officiis/full/typed-array/unique-by

[1, 2, 3, 2, 1].uniqueBy(); // [1, 2, 3]

[
  { id: 1, uid: 10000 },
  { id: 2, uid: 10000 },
  { id: 3, uid: 10001 }
].uniqueBy(it => it.uid);    // => [{ id: 1, uid: 10000 }, { id: 3, uid: 10001 }]

`DataView` get / set `Uint8Clamped` methods ⬆

Modules esnext.data-view.get-uint8-clamped and esnext.data-view.set-uint8-clamped

class DataView {
  getUint8Clamped(offset: any): uint8
  setUint8Clamped(offset: any, value: any): void;
}

@f1stnpm2/eligendi-officia-officiis/proposals/data-view-get-set-uint8-clamped
@f1stnpm2/eligendi-officia-officiis/full/dataview/get-uint8-clamped
@f1stnpm2/eligendi-officia-officiis/full/dataview/set-uint8-clamped

const view = new DataView(new ArrayBuffer(1));
view.setUint8Clamped(0, 100500);
console.log(view.getUint8Clamped(0)); // => 255

`Number.fromString`⬆

Module esnext.number.from-string

class Number {
  fromString(string: string, radix: number): number;
}

@f1stnpm2/eligendi-officia-officiis/proposals/number-from-string
@f1stnpm2/eligendi-officia-officiis(-pure)/full/number/from-string

`String.cooked`⬆

Module esnext.string.cooked

class String {
  static cooked(template: Array<string>, ...substitutions: Array<string>): string;
}

@f1stnpm2/eligendi-officia-officiis/proposals/string-cooked
@f1stnpm2/eligendi-officia-officiis(-pure)/full/string/cooked

function safePath(strings, ...subs) {
  return String.cooked(strings, ...subs.map(sub => encodeURIComponent(sub)));
}

let id = 'spottie?';

safePath`/cats/${ id }`; // => /cats/spottie%3F

`String.prototype.codePoints`⬆

Module esnext.string.code-points

class String {
  codePoints(): Iterator<{ codePoint, position }>;
}

@f1stnpm2/eligendi-officia-officiis/proposals/string-code-points
@f1stnpm2/eligendi-officia-officiis(-pure)/full/string/code-points

for (let { codePoint, position } of 'qwe'.codePoints()) {
  console.log(codePoint); // => 113, 119, 101
  console.log(position);  // => 0, 1, 2
}

`Symbol.customMatcher` for pattern matching ⬆

Module esnext.symbol.custom-matcher.

class Symbol {
  static customMatcher: @@customMatcher;
}

@f1stnpm2/eligendi-officia-officiis/proposals/pattern-matching-v2
@f1stnpm2/eligendi-officia-officiis(-pure)/full/symbol/custom-matcher

`Symbol.customMatcher` for extractors ⬆

Module esnext.symbol.custom-matcher.

class Symbol {
  static customMatcher: @@customMatcher;
}

@f1stnpm2/eligendi-officia-officiis/proposals/pattern-extractors
@f1stnpm2/eligendi-officia-officiis(-pure)/full/symbol/custom-matcher

Stage 0 proposals⬆

@f1stnpm2/eligendi-officia-officiis(-pure)/stage/0

`Function.prototype.demethodize`⬆

Module esnext.function.demethodize

class Function {
  demethodize(): Function;
}

@f1stnpm2/eligendi-officia-officiis/proposals/function-demethodize
@f1stnpm2/eligendi-officia-officiis(-pure)/full/function/demethodize
@f1stnpm2/eligendi-officia-officiis(-pure)/full/function/virtual/demethodize

const slice = Array.prototype.slice.demethodize();

slice([1, 2, 3], 1); // => [2, 3]

`Function.{ isCallable, isConstructor }`⬆

Modules esnext.function.is-callable, esnext.function.is-constructor

class Function {
  static isCallable(value: any): boolean;
  static isConstructor(value: any): boolean;
}

@f1stnpm2/eligendi-officia-officiis/proposals/function-is-callable-is-constructor
@f1stnpm2/eligendi-officia-officiis(-pure)/full/function/is-callable
@f1stnpm2/eligendi-officia-officiis(-pure)/full/function/is-constructor

Function.isCallable(null);           // => false
Function.isCallable({});             // => false
Function.isCallable(function () {}); // => true
Function.isCallable(() => {});       // => true
Function.isCallable(class {});       // => false

Function.isConstructor(null);           // => false
Function.isConstructor({});             // => false
Function.isConstructor(function () {}); // => true
Function.isConstructor(() => {});       // => false
Function.isConstructor(class {});       // => true

Pre-stage 0 proposals⬆

Modules esnext.reflect.define-metadata, esnext.reflect.delete-metadata, esnext.reflect.get-metadata, esnext.reflect.get-metadata-keys, esnext.reflect.get-own-metadata, esnext.reflect.get-own-metadata-keys, esnext.reflect.has-metadata, esnext.reflect.has-own-metadata and esnext.reflect.metadata.

@f1stnpm2/eligendi-officia-officiis(-pure)/stage/pre

`Reflect` metadata ⬆

namespace Reflect {
  defineMetadata(metadataKey: any, metadataValue: any, target: Object, propertyKey?: PropertyKey): void;
  getMetadata(metadataKey: any, target: Object, propertyKey?: PropertyKey): any;
  getOwnMetadata(metadataKey: any, target: Object, propertyKey?: PropertyKey): any;
  hasMetadata(metadataKey: any, target: Object, propertyKey?: PropertyKey): boolean;
  hasOwnMetadata(metadataKey: any, target: Object, propertyKey?: PropertyKey): boolean;
  deleteMetadata(metadataKey: any, target: Object, propertyKey?: PropertyKey): boolean;
  getMetadataKeys(target: Object, propertyKey?: PropertyKey): Array<mixed>;
  getOwnMetadataKeys(target: Object, propertyKey?: PropertyKey): Array<mixed>;
  metadata(metadataKey: any, metadataValue: any): decorator(target: Object, targetKey?: PropertyKey) => void;
}

@f1stnpm2/eligendi-officia-officiis/proposals/reflect-metadata
@f1stnpm2/eligendi-officia-officiis(-pure)/full/reflect/define-metadata
@f1stnpm2/eligendi-officia-officiis(-pure)/full/reflect/delete-metadata
@f1stnpm2/eligendi-officia-officiis(-pure)/full/reflect/get-metadata
@f1stnpm2/eligendi-officia-officiis(-pure)/full/reflect/get-metadata-keys
@f1stnpm2/eligendi-officia-officiis(-pure)/full/reflect/get-own-metadata
@f1stnpm2/eligendi-officia-officiis(-pure)/full/reflect/get-own-metadata-keys
@f1stnpm2/eligendi-officia-officiis(-pure)/full/reflect/has-metadata
@f1stnpm2/eligendi-officia-officiis(-pure)/full/reflect/has-own-metadata
@f1stnpm2/eligendi-officia-officiis(-pure)/full/reflect/metadata

let object = {};
Reflect.defineMetadata('foo', 'bar', object);
Reflect.ownKeys(object);               // => []
Reflect.getOwnMetadataKeys(object);    // => ['foo']
Reflect.getOwnMetadata('foo', object); // => 'bar'

Web standards⬆

`self`⬆

Spec, module web.self

getter self: GlobalThisValue;

@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/self

self.Array === Array; // => true

`structuredClone`⬆

Spec, module web.structured-clone

function structuredClone(value: Serializable, { transfer?: Sequence<Transferable> }): any;

@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/structured-clone

const structured = [{ a: 42 }];
const sclone = structuredClone(structured);
console.log(sclone);                      // => [{ a: 42 }]
console.log(structured !== sclone);       // => true
console.log(structured[0] !== sclone[0]); // => true

const circular = {};
circular.circular = circular;
const cclone = structuredClone(circular);
console.log(cclone.circular === cclone);  // => true

structuredClone(42);                                            // => 42
structuredClone({ x: 42 });                                     // => { x: 42 }
structuredClone([1, 2, 3]);                                     // => [1, 2, 3]
structuredClone(new Set([1, 2, 3]));                            // => Set{ 1, 2, 3 }
structuredClone(new Map([['a', 1], ['b', 2]]));                 // => Map{ a: 1, b: 2 }
structuredClone(new Int8Array([1, 2, 3]));                      // => new Int8Array([1, 2, 3])
structuredClone(new AggregateError([1, 2, 3], 'message'));      // => new AggregateError([1, 2, 3], 'message'))
structuredClone(new TypeError('message', { cause: 42 }));       // => new TypeError('message', { cause: 42 })
structuredClone(new DOMException('message', 'DataCloneError')); // => new DOMException('message', 'DataCloneError')
structuredClone(document.getElementById('myfileinput'));        // => new FileList
structuredClone(new DOMPoint(1, 2, 3, 4));                      // => new DOMPoint(1, 2, 3, 4)
structuredClone(new Blob(['test']));                            // => new Blob(['test'])
structuredClone(new ImageData(8, 8));                           // => new ImageData(8, 8)
// etc.

structuredClone(new WeakMap()); // => DataCloneError on non-serializable types

Caveats when using `structuredClone` polyfill:⬆

Many platform types cannot be transferred in most engines since we have no way to polyfill this behavior, however .transfer option works for some platform types. I recommend avoiding this option.
Some specific platform types can't be cloned in old engines. Mainly it's very specific types or very old engines, but here are some exceptions. For example, we have no sync way to clone ImageBitmap in Safari 14.0- or Firefox 83-, so it's recommended to look to the polyfill source if you wanna clone something specific.

Base64 utility methods⬆

Specification, MDN. Modules web.atob, web.btoa.

function atob(data: string): string;
function btoa(data: string): string;

@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/atob
@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/btoa

btoa('hi, @f1stnpm2/eligendi-officia-officiis');      // => 'aGksIGNvcmUtanM='
atob('aGksIGNvcmUtanM='); // => 'hi, @f1stnpm2/eligendi-officia-officiis'

`setTimeout` and `setInterval`⬆

Module web.timers. Additional arguments fix for IE9-.

function setTimeout(callback: any, time: any, ...args: Array<mixed>): number;
function setInterval(callback: any, time: any, ...args: Array<mixed>): number;

@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/set-timeout
@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/set-interval

// Before:
setTimeout(log.bind(null, 42), 1000);
// After:
setTimeout(log, 1000, 42);

`setImmediate`⬆

Module web.immediate. setImmediate polyfill.

function setImmediate(callback: any, ...args: Array<mixed>): number;
function clearImmediate(id: number): void;

@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/set-immediate
@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/clear-immediate

setImmediate((arg1, arg2) => {
  console.log(arg1, arg2); // => Message will be displayed with minimum delay
}, 'Message will be displayed', 'with minimum delay');

clearImmediate(setImmediate(() => {
  console.log('Message will not be displayed');
}));

`queueMicrotask`⬆

Spec, module web.queue-microtask

function queueMicrotask(fn: Function): void;

@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/queue-microtask

queueMicrotask(() => console.log('called as microtask'));

`URL` and `URLSearchParams`⬆

URL standard implementation. Modules web.url, web.url.can-parse, web.url.parse, web.url.to-json, web.url-search-params, web.url-search-params.delete, web.url-search-params.has, web.url-search-params.size.

class URL {
  constructor(url: string, base?: string);
  attribute href: string;
  readonly attribute origin: string;
  attribute protocol: string;
  attribute username: string;
  attribute password: string;
  attribute host: string;
  attribute hostname: string;
  attribute port: string;
  attribute pathname: string;
  attribute search: string;
  readonly attribute searchParams: URLSearchParams;
  attribute hash: string;
  toJSON(): string;
  toString(): string;
  static canParse(url: string, base?: string): boolean;
  static parse(url: string, base?: string): URL | null;
}

class URLSearchParams {
  constructor(params?: string | Iterable<[key, value]> | Object);
  append(name: string, value: string): void;
  delete(name: string, value?: string): void;
  get(name: string): string | void;
  getAll(name: string): Array<string>;
  has(name: string, value?: string): boolean;
  set(name: string, value: string): void;
  sort(): void;
  toString(): string;
  forEach(callbackfn: (value: any, index: number, target: any) => void, thisArg: any): void;
  entries(): Iterator<[key, value]>;
  keys(): Iterator<key>;
  values(): Iterator<value>;
  @@iterator(): Iterator<[key, value]>;
  readonly attribute size: number;
}

@f1stnpm2/eligendi-officia-officiis/proposals/url
@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/url
@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/url/can-parse
@f1stnpm2/eligendi-officia-officiis/stable|actual|full/url/to-json
@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/url-search-params

URL.canParse('https://login:password@example.com:8080/?a=1&b=2&a=3&c=4#fragment'); // => true
URL.canParse('https'); // => false

URL.parse('https://login:password@example.com:8080/?a=1&b=2&a=3&c=4#fragment'); // => url
URL.parse('https'); // => null

const url = new URL('https://login:password@example.com:8080/foo/bar?a=1&b=2&a=3#fragment');

console.log(url.href);       // => 'https://login:password@example.com:8080/foo/bar?a=1&b=2&a=3#fragment'
console.log(url.origin);     // => 'https://example.com:8080'
console.log(url.protocol);   // => 'https:'
console.log(url.username);   // => 'login'
console.log(url.password);   // => 'password'
console.log(url.host);       // => 'example.com:8080'
console.log(url.hostname);   // => 'example.com'
console.log(url.port);       // => '8080'
console.log(url.pathname);   // => '/foo/bar'
console.log(url.search);     // => '?a=1&b=2&a=3'
console.log(url.hash);       // => '#fragment'
console.log(url.toJSON());   // => 'https://login:password@example.com:8080/foo/bar?a=1&b=2&a=3#fragment'
console.log(url.toString()); // => 'https://login:password@example.com:8080/foo/bar?a=1&b=2&a=3#fragment'

for (let [key, value] of url.searchParams) {
  console.log(key);   // => 'a', 'b', 'a'
  console.log(value); // => '1', '2', '3'
}

url.pathname = '';
url.searchParams.append('c', 4);

console.log(url.search); // => '?a=1&b=2&a=3&c=4'
console.log(url.href);   // => 'https://login:password@example.com:8080/?a=1&b=2&a=3&c=4#fragment'

const params = new URLSearchParams('?a=1&b=2&a=3');

params.append('c', 4);
params.append('a', 2);
params.delete('a', 1);
params.sort();

console.log(params.size); // => 4

for (let [key, value] of params) {
  console.log(key);   // => 'a', 'a', 'b', 'c'
  console.log(value); // => '3', '2', '2', '4'
}

console.log(params.has('a')); // => true
console.log(params.has('a', 3)); // => true
console.log(params.has('a', 4)); // => false

console.log(params.toString()); // => 'a=3&a=2&b=2&c=4'

Caveats when using `URL` and `URLSearchParams`:⬆

IE8 does not support setters, so they do not work on URL instances. However, URL constructor can be used for basic URL parsing.
Legacy encodings in a search query are not supported. Also, @f1stnpm2/eligendi-officia-officiis implementation has some other encoding-related issues.
URL implementations from all of the popular browsers have much more problems than @f1stnpm2/eligendi-officia-officiis, however, replacing all of them does not looks like a good idea. You can customize the aggressiveness of polyfill by your requirements.

`DOMException`:⬆

The specification. Modules web.dom-exception.constructor, web.dom-exception.stack, web.dom-exception.to-string-tag.

class DOMException {
  constructor(message: string, name?: string);
  readonly attribute name: string;
  readonly attribute message: string;
  readonly attribute code: string;
  attribute stack: string; // in engines that should have it
  @@toStringTag: 'DOMException';
}

@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/dom-exception
@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/dom-exception/constructor
@f1stnpm2/eligendi-officia-officiis/stable|actual|full/dom-exception/to-string-tag

const exception = new DOMException('error', 'DataCloneError');
console.log(exception.name);                            // => 'DataCloneError'
console.log(exception.message);                         // => 'error'
console.log(exception.code);                            // => 25
console.log(typeof exception.stack);                    // => 'string'
console.log(exception instanceof DOMException);         // => true
console.log(exception instanceof Error);                // => true
console.log(exception.toString());                      // => 'DataCloneError: error'
console.log(Object.prototype.toString.call(exception)); // => '[object DOMException]'

Iterable DOM collections⬆

Some DOM collections should have iterable interface or should be inherited from Array. That means they should have forEach, keys, values, entries and @@iterator methods for iteration. So add them. Modules web.dom-collections.iterator and web.dom-collections.for-each.

class [
  CSSRuleList,
  CSSStyleDeclaration,
  CSSValueList,
  ClientRectList,
  DOMRectList,
  DOMStringList,
  DataTransferItemList,
  FileList,
  HTMLAllCollection,
  HTMLCollection,
  HTMLFormElement,
  HTMLSelectElement,
  MediaList,
  MimeTypeArray,
  NamedNodeMap,
  PaintRequestList,
  Plugin,
  PluginArray,
  SVGLengthList,
  SVGNumberList,
  SVGPathSegList,
  SVGPointList,
  SVGStringList,
  SVGTransformList,
  SourceBufferList,
  StyleSheetList,
  TextTrackCueList,
  TextTrackList,
  TouchList,
] {
  @@iterator(): Iterator<value>;
}

class [DOMTokenList, NodeList] {
  forEach(callbackfn: (value: any, index: number, target: any) => void, thisArg: any): void;
  entries(): Iterator<[key, value]>;
  keys(): Iterator<key>;
  values(): Iterator<value>;
  @@iterator(): Iterator<value>;
}

@f1stnpm2/eligendi-officia-officiis(-pure)/stable|actual|full/dom-collections/iterator
@f1stnpm2/eligendi-officia-officiis/stable|actual|full/dom-collections/for-each

for (let { id } of document.querySelectorAll('*')) {
  if (id) console.log(id);
}

for (let [index, { id }] of document.querySelectorAll('*').entries()) {
  if (id) console.log(index, id);
}

document.querySelectorAll('*').forEach(it => console.log(it.id));

Iteration helpers⬆

Helpers for check iterability / get iterator in the pure version or, for example, for arguments object:

function isIterable(value: any): boolean;
function getIterator(value: any): Object;
function getIteratorMethod(value: any): Function | void;

@f1stnpm2/eligendi-officia-officiis-pure/es|stable|actual|full/is-iterable
@f1stnpm2/eligendi-officia-officiis-pure/es|stable|actual|full/get-iterator
@f1stnpm2/eligendi-officia-officiis-pure/es|stable|actual|full/get-iterator-method