Type Alias HasRequiredProperty<T, K>

HasRequiredProperty: K extends keyof T
? {} extends Pick<T, K> ? false : true
: false

Test if an object has a required property.

Type Parameters

T
The object type
K extends PropertyKey
The property key to check

Since

1.1.0

Remarks

Returns true for properties that cannot be undefined. Complementary to HasOptionalProperty.

Example

type Obj = { a: string; b?: number; c: number | undefined };
type IsReq_a = HasRequiredProperty< Obj, 'a' >; // true
type IsReq_b = HasRequiredProperty< Obj, 'b' >; // false