Code Reference

Utility Type Methods

TypeScript · Methods reference

TypeScript · Methods reference

📋 Overview

Built-in generic utility types — the “methods” of the type system for transforms.

🔧 Methods

Object utilities

UtilityDescription
Partial<T>All properties optional
Required<T>All properties required
Readonly<T>All properties readonly
Pick<T, K>Subset of keys K
Omit<T, K>T without keys K
Record<K, V>Object type with keys K and values V
Exclude<T, U>Remove from T assignable to U
Extract<T, U>Keep in T assignable to U
NonNullable<T>Remove null and undefined
ReturnType<F>Function return type
Parameters<F>Function parameter tuple
ConstructorParameters<C>Constructor args tuple
InstanceType<C>Instance type of constructor
ThisParameterType<F>this type of function
OmitThisParameter<F>Function without this param
Awaited<T>Unwrap Promise nested type
Uppercase<S> / Lowercase<S> / Capitalize / UncapitalizeString type transforms

💡 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.

🔗 Related

Type Operators

TypeScript · Methods reference

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📋 Overview🔧 MethodsObject utilities💡 Examples⚠️ Pitfalls🔗 Related