Array & Object Methods (Typed)

TypeScript · Methods reference

TypeScript · Methods reference

📋 Overview

Runtime methods same as JavaScript; TypeScript adds typed array helpers and readonly variants.

🔧 Methods

Typed array helpers

API	Description
`ReadonlyArray<T>` / `readonly T[]`	Immutable array type
`Readonly<T>`	Shallow readonly object
`Array<T>` / `T[]`	Mutable array syntax
`Tuple` types `[T, U]`	Fixed-length typed arrays
`as const` tuples	Literal readonly tuples
`.includes()` narrowing	With literal union and `as const`
`NoInfer<T>`	Block inference in generics (5.4+)

Same as JS (see JS Methods)

Category	Link concept
Array prototype	map, filter, reduce, find, …
String prototype	slice, split, replace, …
Object static	keys, entries, assign, …
Promise static	all, race, allSettled, …

💡 Examples

See parent topic notes for runnable snippets; this page is the complete method index.

⚠️ Pitfalls

Mutating methods return None in Python — do not chain sort() / reverse() expecting a new list.
Default JS sort() compares strings — pass (a,b) => a-b for numbers.
SQL function names differ by dialect — verify Postgres vs MySQL docs.
Django QuerySet.update() skips save() signals and auto auto_now fields on models.

Arrays (JS)

Methods

TypeScript · Methods

Class & Interface Methods

TypeScript · Methods reference

On this page

📋 Overview 🔧 Methods Typed array helpers Same as JS (see JS Methods)💡 Examples ⚠️ Pitfalls 🔗 Related