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=== tests/cases/conformance/types/rest/genericRestParameters3.ts ===
declare let f1: (x: string, ...args: [string] | [number, boolean]) => void;
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
>x : string
>args : [string] | [number, boolean]
declare let f2: (x: string, y: string) => void;
>f2 : (x: string, y: string) => void
>x : string
>y : string
declare let f3: (x: string, y: number, z: boolean) => void;
>f3 : (x: string, y: number, z: boolean) => void
>x : string
>y : number
>z : boolean
declare let f4: (...args: [string, string] | [string, number, boolean]) => void;
>f4 : (...args: [string, string] | [string, number, boolean]) => void
>args : [string, string] | [string, number, boolean]
declare const t1: [string] | [number, boolean];
>t1 : [string] | [number, boolean]
declare const t2: readonly [string] | [number, boolean];
>t2 : [number, boolean] | readonly [string]
declare const t3: [string] | readonly [number, boolean];
>t3 : [string] | readonly [number, boolean]
declare const t4: readonly [string] | readonly [number, boolean];
>t4 : readonly [string] | readonly [number, boolean]
f1("foo", "abc");
>f1("foo", "abc") : void
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
>"foo" : "foo"
>"abc" : "abc"
f1("foo", 10, true);
>f1("foo", 10, true) : void
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
>"foo" : "foo"
>10 : 10
>true : true
f1("foo", ...t1);
>f1("foo", ...t1) : void
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
>"foo" : "foo"
>...t1 : string | number | boolean
>t1 : [string] | [number, boolean]
f1("foo", ...t2);
>f1("foo", ...t2) : void
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
>"foo" : "foo"
>...t2 : string | number | boolean
>t2 : [number, boolean] | readonly [string]
f1("foo", ...t3);
>f1("foo", ...t3) : void
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
>"foo" : "foo"
>...t3 : string | number | boolean
>t3 : [string] | readonly [number, boolean]
f1("foo", ...t4);
>f1("foo", ...t4) : void
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
>"foo" : "foo"
>...t4 : string | number | boolean
>t4 : readonly [string] | readonly [number, boolean]
f1("foo", 10); // Error
>f1("foo", 10) : void
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
>"foo" : "foo"
>10 : 10
f1("foo"); // Error
>f1("foo") : void
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
>"foo" : "foo"
f2 = f1;
>f2 = f1 : (x: string, ...args: [string] | [number, boolean]) => void
>f2 : (x: string, y: string) => void
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
f3 = f1;
>f3 = f1 : (x: string, ...args: [string] | [number, boolean]) => void
>f3 : (x: string, y: number, z: boolean) => void
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
f4 = f1;
>f4 = f1 : (x: string, ...args: [string] | [number, boolean]) => void
>f4 : (...args: [string, string] | [string, number, boolean]) => void
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
f1 = f2; // Error
>f1 = f2 : (x: string, y: string) => void
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
>f2 : (x: string, y: string) => void
f1 = f3; // Error
>f1 = f3 : (x: string, y: number, z: boolean) => void
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
>f3 : (x: string, y: number, z: boolean) => void
f1 = f4;
>f1 = f4 : (...args: [string, string] | [string, number, boolean]) => void
>f1 : (x: string, ...args: [string] | [number, boolean]) => void
>f4 : (...args: [string, string] | [string, number, boolean]) => void
// Repro from #26110
interface CoolArray<E> extends Array<E> {
hello: number;
>hello : number
}
declare function foo<T extends any[]>(cb: (...args: T) => void): void;
>foo : <T extends any[]>(cb: (...args: T) => void) => void
>cb : (...args: T) => void
>args : T
foo<CoolArray<any>>(); // Error
>foo<CoolArray<any>>() : void
>foo : <T extends any[]>(cb: (...args: T) => void) => void
foo<CoolArray<any>>(100); // Error
>foo<CoolArray<any>>(100) : void
>foo : <T extends any[]>(cb: (...args: T) => void) => void
>100 : 100
foo<CoolArray<any>>(foo); // Error
>foo<CoolArray<any>>(foo) : void
>foo : <T extends any[]>(cb: (...args: T) => void) => void
>foo : <T extends any[]>(cb: (...args: T) => void) => void
function bar<T extends any[]>(...args: T): T {
>bar : <T extends any[]>(...args: T) => T
>args : T
return args;
>args : T
}
let a = bar(10, 20);
>a : [number, number]
>bar(10, 20) : [number, number]
>bar : <T extends any[]>(...args: T) => T
>10 : 10
>20 : 20
let b = bar<CoolArray<number>>(10, 20); // Error
>b : CoolArray<number>
>bar<CoolArray<number>>(10, 20) : CoolArray<number>
>bar : <T extends any[]>(...args: T) => T
>10 : 10
>20 : 20
declare function baz<T>(...args: CoolArray<T>): void;
>baz : <T>(...args: CoolArray<T>) => void
>args : CoolArray<T>
declare const ca: CoolArray<number>;
>ca : CoolArray<number>
baz(); // Error
>baz() : void
>baz : <T>(...args: CoolArray<T>) => void
baz(1); // Error
>baz(1) : void
>baz : <T>(...args: CoolArray<T>) => void
>1 : 1
baz(1, 2); // Error
>baz(1, 2) : void
>baz : <T>(...args: CoolArray<T>) => void
>1 : 1
>2 : 2
baz(...ca); // Error
>baz(...ca) : void
>baz : <T>(...args: CoolArray<T>) => void
>...ca : number
>ca : CoolArray<number>
// Repro from #26491
declare function hmm<A extends [] | [number, string]>(...args: A): void;
>hmm : <A extends [] | [number, string]>(...args: A) => void
>args : A
hmm(); // okay, A = []
>hmm() : void
>hmm : <A extends [] | [number, string]>(...args: A) => void
hmm(1, "s"); // okay, A = [1, "s"]
>hmm(1, "s") : void
>hmm : <A extends [] | [number, string]>(...args: A) => void
>1 : 1
>"s" : "s"
hmm("what"); // no error? A = [] | [number, string] ?
>hmm("what") : void
>hmm : <A extends [] | [number, string]>(...args: A) => void
>"what" : "what"
// Repro from #35066
declare function foo2(...args: string[] | number[]): void;
>foo2 : (...args: string[] | number[]) => void
>args : string[] | number[]
let x2: ReadonlyArray<string> = ["hello"];
>x2 : readonly string[]
>["hello"] : string[]
>"hello" : "hello"
foo2(...x2);
>foo2(...x2) : void
>foo2 : (...args: string[] | number[]) => void
>...x2 : string
>x2 : readonly string[]
// Repros from #47754
type RestParams = [y: string] | [y: number];
>RestParams : [y: string] | [y: number]
type Signature = (x: string, ...rest: RestParams) => void;
>Signature : (x: string, ...rest: RestParams) => void
>x : string
>rest : RestParams
type MergedParams = Parameters<Signature>; // [x: string, y: string] | [x: string, y: number]
>MergedParams : [x: string, y: string] | [x: string, y: number]
declare let ff1: (...rest: [string, string] | [string, number]) => void;
>ff1 : (...rest: [string, string] | [string, number]) => void
>rest : [string, string] | [string, number]
declare let ff2: (x: string, ...rest: [string] | [number]) => void;
>ff2 : (x: string, ...rest: [string] | [number]) => void
>x : string
>rest : [string] | [number]
ff1 = ff2;
>ff1 = ff2 : (x: string, ...rest: [string] | [number]) => void
>ff1 : (...rest: [string, string] | [string, number]) => void
>ff2 : (x: string, ...rest: [string] | [number]) => void
ff2 = ff1;
>ff2 = ff1 : (...rest: [string, string] | [string, number]) => void
>ff2 : (x: string, ...rest: [string] | [number]) => void
>ff1 : (...rest: [string, string] | [string, number]) => void
function ff3<A extends unknown[]>(s1: (...args: [x: string, ...rest: A | [number]]) => void, s2: (x: string, ...rest: A | [number]) => void) {
>ff3 : <A extends unknown[]>(s1: (...args: [x: string, ...rest: A | [number]]) => void, s2: (x: string, ...rest: A | [number]) => void) => void
>s1 : (...args: [x: string, ...rest: A | [number]]) => void
>args : [string, number] | [x: string, ...rest: A]
>s2 : (x: string, ...rest: A | [number]) => void
>x : string
>rest : [number] | A
s1 = s2;
>s1 = s2 : (x: string, ...rest: [number] | A) => void
>s1 : (...args: [string, number] | [x: string, ...rest: A]) => void
>s2 : (x: string, ...rest: [number] | A) => void
s2 = s1;
>s2 = s1 : (...args: [string, number] | [x: string, ...rest: A]) => void
>s2 : (x: string, ...rest: [number] | A) => void
>s1 : (...args: [string, number] | [x: string, ...rest: A]) => void
}
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