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=== tests/cases/conformance/types/mapped/mappedTypeAsClauses.ts ===
// Mapped type 'as N' clauses
type Getters<T> = { [P in keyof T & string as `get${Capitalize<P>}`]: () => T[P] };
>Getters : Getters<T>
type TG1 = Getters<{ foo: string, bar: number, baz: { z: boolean } }>;
>TG1 : Getters<{ foo: string; bar: number; baz: { z: boolean;}; }>
>foo : string
>bar : number
>baz : { z: boolean; }
>z : boolean
// Mapped type with 'as N' clause has no constraint on 'in T' clause
type PropDef<K extends keyof any, T> = { name: K, type: T };
>PropDef : PropDef<K, T>
>name : K
>type : T
type TypeFromDefs<T extends PropDef<keyof any, any>> = { [P in T as P['name']]: P['type'] };
>TypeFromDefs : TypeFromDefs<T>
type TP1 = TypeFromDefs<{ name: 'a', type: string } | { name: 'b', type: number } | { name: 'a', type: boolean }>;
>TP1 : TypeFromDefs<{ name: 'a'; type: string; } | { name: 'b'; type: number; } | { name: 'a'; type: boolean; }>
>name : "a"
>type : string
>name : "b"
>type : number
>name : "a"
>type : boolean
// No array or tuple type mapping when 'as N' clause present
type TA1 = Getters<string[]>;
>TA1 : Getters<string[]>
type TA2 = Getters<[number, boolean]>;
>TA2 : Getters<[number, boolean]>
// Filtering using 'as N' clause
type Methods<T> = { [P in keyof T as T[P] extends Function ? P : never]: T[P] };
>Methods : Methods<T>
type TM1 = Methods<{ foo(): number, bar(x: string): boolean, baz: string | number }>;
>TM1 : Methods<{ foo(): number; bar(x: string): boolean; baz: string | number; }>
>foo : () => number
>bar : (x: string) => boolean
>x : string
>baz : string | number
// Mapping to multiple names using 'as N' clause
type DoubleProp<T> = { [P in keyof T & string as `${P}1` | `${P}2`]: T[P] }
>DoubleProp : DoubleProp<T>
type TD1 = DoubleProp<{ a: string, b: number }>; // { a1: string, a2: string, b1: number, b2: number }
>TD1 : DoubleProp<{ a: string; b: number; }>
>a : string
>b : number
type TD2 = keyof TD1; // 'a1' | 'a2' | 'b1' | 'b2'
>TD2 : "a1" | "a2" | "b1" | "b2"
type TD3<U> = keyof DoubleProp<U>; // `${keyof U & string}1` | `${keyof U & string}2`
>TD3 : `${keyof U & string}1` | `${keyof U & string}2`
// Repro from #40619
type Lazyify<T> = {
>Lazyify : Lazyify<T>
[K in keyof T as `get${Capitalize<K & string>}`]: () => T[K]
};
interface Person {
readonly name: string;
>name : string
age: number;
>age : number
location?: string;
>location : string | undefined
}
type LazyPerson = Lazyify<Person>;
>LazyPerson : Lazyify<Person>
// Repro from #40833
type Example = {foo: string, bar: number};
>Example : Example
>foo : string
>bar : number
type PickByValueType<T, U> = {
>PickByValueType : PickByValueType<T, U>
[K in keyof T as T[K] extends U ? K : never]: T[K]
};
type T1 = PickByValueType<Example, string>;
>T1 : PickByValueType<Example, string>
const e1: T1 = {
>e1 : PickByValueType<Example, string>
>{ foo: "hello"} : { foo: string; }
foo: "hello"
>foo : string
>"hello" : "hello"
};
type T2 = keyof T1;
>T2 : "foo"
const e2: T2 = "foo";
>e2 : "foo"
>"foo" : "foo"
// Repro from #41133
interface Car {
name: string;
>name : string
seats: number;
>seats : number
engine: Engine;
>engine : Engine
wheels: Wheel[];
>wheels : Wheel[]
}
interface Engine {
manufacturer: string;
>manufacturer : string
horsepower: number;
>horsepower : number
}
interface Wheel {
type: "summer" | "winter";
>type : "summer" | "winter"
radius: number;
>radius : number
}
type Primitive = string | number | boolean;
>Primitive : Primitive
type OnlyPrimitives<T> = { [K in keyof T as T[K] extends Primitive ? K : never]: T[K] };
>OnlyPrimitives : OnlyPrimitives<T>
let primitiveCar: OnlyPrimitives<Car>; // { name: string; seats: number; }
>primitiveCar : OnlyPrimitives<Car>
let keys: keyof OnlyPrimitives<Car>; // "name" | "seats"
>keys : "name" | "seats"
type KeysOfPrimitives<T> = keyof OnlyPrimitives<T>;
>KeysOfPrimitives : keyof OnlyPrimitives<T>
let carKeys: KeysOfPrimitives<Car>; // "name" | "seats"
>carKeys : "name" | "seats"
|
