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Required<T>

Constructs a type with all properties of T set to required.

Since TS 2.8 Spec ↗

Syntax

Required<Type>

Returns

object type — A new type identical to T but with every optional property made required.

Examples

interface Props {
  a?: number;
  b?: string;
}

const obj: Required<Props> = { a: 1, b: 'x' };

type Settings = { theme?: string; debug?: boolean };
function applyAll(s: Required<Settings>) {
  console.log(s.theme, s.debug);
}

Notes

Removes the `?` modifier from every property using a `-?` mapped type. Shallow only; nested optional members remain optional. It also strips `undefined` that was added implicitly by the optional modifier, but not explicit `| undefined` unions in property types.

See also