Guided Notes

Utility Types

The built-in type helpers β€” Partial, Required, Readonly, Pick, Omit, Record, Exclude, Extract, NonNullable, ReturnType, Parameters and Awaited β€” with real use cases.

Transforming object types

Slide 1 / 4
UtilityResultTypical use
Partial<T>All properties optionalUpdate/patch payloads
Required<T>All properties requiredAfter defaults are applied
Readonly<T>All properties readonlyFrozen config, state
Pick<T, K>Only the listed keysPublic view of a model
Omit<T, K>All except the listed keysCreate input without id/createdAt
Record<K, V>Object with keys K, values VLookup tables
← Generics