I have this interface, and I would like to generate a new type from the type of keys it contains.
interface SomeType {
abc: string;
def: number;
ghi: boolean;
}
Type to generate:
type SomeOtherType = string | number | boolean
Is this possible in typescript?
You can try to index with a keyof operator:
interface SomeType {
abc: string;
def: number;
ghi: "sdf";
}
type t = SomeType[keyof SomeType];
The type t will be assumed as a type union that comes from the values of the object:
You can use a trick to generate the values of an interface:
interface SomeType {
abc: string;
def: number;
ghi: boolean;
}
//First generate a type that works as a "valueof" (similar to keyof)
type ValueOf<T> = T[keyof T];
//Then obtain the values
type Values = ValueOf<SomeType> // Values = string | number | boolean
//ValueOf re-usable component, however it is enough also SomeType[keyof SomeType]
//If you need the keys on the other hand "keyof" is enough:
type Keys = keyof SomeType // Keys = 'abc' | 'def' | 'ghi'