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=== tests/cases/conformance/types/typeParameters/typeParameterLists/typeParameterConstModifiers.ts ===
declare function f1<const T>(x: T): T;
>f1 : <const T>(x: T) => T
>x : T
const x11 = f1('a');
>x11 : "a"
>f1('a') : "a"
>f1 : <const T>(x: T) => T
>'a' : "a"
const x12 = f1(['a', ['b', 'c']]);
>x12 : readonly ["a", readonly ["b", "c"]]
>f1(['a', ['b', 'c']]) : readonly ["a", readonly ["b", "c"]]
>f1 : <const T>(x: T) => T
>['a', ['b', 'c']] : ["a", ["b", "c"]]
>'a' : "a"
>['b', 'c'] : ["b", "c"]
>'b' : "b"
>'c' : "c"
const x13 = f1({ a: 1, b: "c", d: ["e", 2, true, { f: "g" }] });
>x13 : { readonly a: 1; readonly b: "c"; readonly d: readonly ["e", 2, true, { readonly f: "g"; }]; }
>f1({ a: 1, b: "c", d: ["e", 2, true, { f: "g" }] }) : { readonly a: 1; readonly b: "c"; readonly d: readonly ["e", 2, true, { readonly f: "g"; }]; }
>f1 : <const T>(x: T) => T
>{ a: 1, b: "c", d: ["e", 2, true, { f: "g" }] } : { a: 1; b: "c"; d: ["e", 2, true, { f: "g"; }]; }
>a : 1
>1 : 1
>b : "c"
>"c" : "c"
>d : ["e", 2, true, { f: "g"; }]
>["e", 2, true, { f: "g" }] : ["e", 2, true, { f: "g"; }]
>"e" : "e"
>2 : 2
>true : true
>{ f: "g" } : { f: "g"; }
>f : "g"
>"g" : "g"
declare function f2<const T, U>(x: T | undefined): T;
>f2 : <const T, U>(x: T | undefined) => T
>x : T | undefined
const x21 = f2('a');
>x21 : "a"
>f2('a') : "a"
>f2 : <const T, U>(x: T | undefined) => T
>'a' : "a"
const x22 = f2(['a', ['b', 'c']]);
>x22 : readonly ["a", readonly ["b", "c"]]
>f2(['a', ['b', 'c']]) : readonly ["a", readonly ["b", "c"]]
>f2 : <const T, U>(x: T | undefined) => T
>['a', ['b', 'c']] : ["a", ["b", "c"]]
>'a' : "a"
>['b', 'c'] : ["b", "c"]
>'b' : "b"
>'c' : "c"
const x23 = f2({ a: 1, b: "c", d: ["e", 2, true, { f: "g" }] });
>x23 : { readonly a: 1; readonly b: "c"; readonly d: readonly ["e", 2, true, { readonly f: "g"; }]; }
>f2({ a: 1, b: "c", d: ["e", 2, true, { f: "g" }] }) : { readonly a: 1; readonly b: "c"; readonly d: readonly ["e", 2, true, { readonly f: "g"; }]; }
>f2 : <const T, U>(x: T | undefined) => T
>{ a: 1, b: "c", d: ["e", 2, true, { f: "g" }] } : { a: 1; b: "c"; d: ["e", 2, true, { f: "g"; }]; }
>a : 1
>1 : 1
>b : "c"
>"c" : "c"
>d : ["e", 2, true, { f: "g"; }]
>["e", 2, true, { f: "g" }] : ["e", 2, true, { f: "g"; }]
>"e" : "e"
>2 : 2
>true : true
>{ f: "g" } : { f: "g"; }
>f : "g"
>"g" : "g"
declare function f3<const T>(x: T): T[];
>f3 : <const T>(x: T) => T[]
>x : T
const x31 = f3("hello");
>x31 : "hello"[]
>f3("hello") : "hello"[]
>f3 : <const T>(x: T) => T[]
>"hello" : "hello"
const x32 = f3("hello");
>x32 : "hello"[]
>f3("hello") : "hello"[]
>f3 : <const T>(x: T) => T[]
>"hello" : "hello"
declare function f4<const T>(obj: [T, T]): T;
>f4 : <const T>(obj: [T, T]) => T
>obj : [T, T]
const x41 = f4([[1, 'x'], [2, 'y']]);
>x41 : readonly [1, "x"] | readonly [2, "y"]
>f4([[1, 'x'], [2, 'y']]) : readonly [1, "x"] | readonly [2, "y"]
>f4 : <const T>(obj: [T, T]) => T
>[[1, 'x'], [2, 'y']] : [[1, "x"], [2, "y"]]
>[1, 'x'] : [1, "x"]
>1 : 1
>'x' : "x"
>[2, 'y'] : [2, "y"]
>2 : 2
>'y' : "y"
const x42 = f4([{ a: 1, b: 'x' }, { a: 2, b: 'y' }]);
>x42 : { readonly a: 1; readonly b: "x"; } | { readonly a: 2; readonly b: "y"; }
>f4([{ a: 1, b: 'x' }, { a: 2, b: 'y' }]) : { readonly a: 1; readonly b: "x"; } | { readonly a: 2; readonly b: "y"; }
>f4 : <const T>(obj: [T, T]) => T
>[{ a: 1, b: 'x' }, { a: 2, b: 'y' }] : [{ a: 1; b: "x"; }, { a: 2; b: "y"; }]
>{ a: 1, b: 'x' } : { a: 1; b: "x"; }
>a : 1
>1 : 1
>b : "x"
>'x' : "x"
>{ a: 2, b: 'y' } : { a: 2; b: "y"; }
>a : 2
>2 : 2
>b : "y"
>'y' : "y"
declare function f5<const T>(obj: { x: T, y: T }): T;
>f5 : <const T>(obj: { x: T; y: T;}) => T
>obj : { x: T; y: T; }
>x : T
>y : T
const x51 = f5({ x: [1, 'x'], y: [2, 'y'] });
>x51 : readonly [1, "x"] | readonly [2, "y"]
>f5({ x: [1, 'x'], y: [2, 'y'] }) : readonly [1, "x"] | readonly [2, "y"]
>f5 : <const T>(obj: { x: T; y: T; }) => T
>{ x: [1, 'x'], y: [2, 'y'] } : { x: [1, "x"]; y: [2, "y"]; }
>x : [1, "x"]
>[1, 'x'] : [1, "x"]
>1 : 1
>'x' : "x"
>y : [2, "y"]
>[2, 'y'] : [2, "y"]
>2 : 2
>'y' : "y"
const x52 = f5({ x: { a: 1, b: 'x' }, y: { a: 2, b: 'y' } });
>x52 : { readonly a: 1; readonly b: "x"; } | { readonly a: 2; readonly b: "y"; }
>f5({ x: { a: 1, b: 'x' }, y: { a: 2, b: 'y' } }) : { readonly a: 1; readonly b: "x"; } | { readonly a: 2; readonly b: "y"; }
>f5 : <const T>(obj: { x: T; y: T; }) => T
>{ x: { a: 1, b: 'x' }, y: { a: 2, b: 'y' } } : { x: { a: 1; b: "x"; }; y: { a: 2; b: "y"; }; }
>x : { a: 1; b: "x"; }
>{ a: 1, b: 'x' } : { a: 1; b: "x"; }
>a : 1
>1 : 1
>b : "x"
>'x' : "x"
>y : { a: 2; b: "y"; }
>{ a: 2, b: 'y' } : { a: 2; b: "y"; }
>a : 2
>2 : 2
>b : "y"
>'y' : "y"
declare function f6<const T extends readonly unknown[]>(...args: T): T;
>f6 : <const T extends readonly unknown[]>(...args: T) => T
>args : T
const x61 = f6(1, 'b', { a: 1, b: 'x' });
>x61 : readonly [1, "b", { readonly a: 1; readonly b: "x"; }]
>f6(1, 'b', { a: 1, b: 'x' }) : readonly [1, "b", { readonly a: 1; readonly b: "x"; }]
>f6 : <const T extends readonly unknown[]>(...args: T) => T
>1 : 1
>'b' : "b"
>{ a: 1, b: 'x' } : { a: 1; b: "x"; }
>a : 1
>1 : 1
>b : "x"
>'x' : "x"
class C1<const T> {
>C1 : C1<T>
constructor(x: T) {}
>x : T
foo<const U>(x: U) { return x; }
>foo : <const U>(x: U) => U
>x : U
>x : U
}
const c71 = new C1({ a: 1, b: "c", d: ["e", 2, true, { f: "g" }] });
>c71 : C1<{ readonly a: 1; readonly b: "c"; readonly d: readonly ["e", 2, true, { readonly f: "g"; }]; }>
>new C1({ a: 1, b: "c", d: ["e", 2, true, { f: "g" }] }) : C1<{ readonly a: 1; readonly b: "c"; readonly d: readonly ["e", 2, true, { readonly f: "g"; }]; }>
>C1 : typeof C1
>{ a: 1, b: "c", d: ["e", 2, true, { f: "g" }] } : { a: 1; b: "c"; d: ["e", 2, true, { f: "g"; }]; }
>a : 1
>1 : 1
>b : "c"
>"c" : "c"
>d : ["e", 2, true, { f: "g"; }]
>["e", 2, true, { f: "g" }] : ["e", 2, true, { f: "g"; }]
>"e" : "e"
>2 : 2
>true : true
>{ f: "g" } : { f: "g"; }
>f : "g"
>"g" : "g"
const c72 = c71.foo(['a', ['b', 'c']]);
>c72 : readonly ["a", readonly ["b", "c"]]
>c71.foo(['a', ['b', 'c']]) : readonly ["a", readonly ["b", "c"]]
>c71.foo : <const U>(x: U) => U
>c71 : C1<{ readonly a: 1; readonly b: "c"; readonly d: readonly ["e", 2, true, { readonly f: "g"; }]; }>
>foo : <const U>(x: U) => U
>['a', ['b', 'c']] : ["a", ["b", "c"]]
>'a' : "a"
>['b', 'c'] : ["b", "c"]
>'b' : "b"
>'c' : "c"
const C2 = class <const T> {}
>C2 : typeof C2
>class <const T> {} : typeof C2
const fx1 = <const T>(x: T) => x;
>fx1 : <const T>(x: T) => T
><const T>(x: T) => x : <const T>(x: T) => T
>x : T
>x : T
const fx2 = <const T,>(x: T) => x;
>fx2 : <const T>(x: T) => T
><const T,>(x: T) => x : <const T>(x: T) => T
>x : T
>x : T
interface I1<const T> { x: T } // Error
>x : T
interface I2 {
f<const T>(x: T): T;
>f : <const T>(x: T) => T
>x : T
}
type T1<const T> = T; // Error
>T1 : T
type T2 = <const T>(x: T) => T;
>T2 : <const T>(x: T) => T
>x : T
type T3 = { <const T>(x: T): T };
>T3 : <const T>(x: T) => T
>x : T
type T4 = new <const T>(x: T) => T;
>T4 : new <const T>(x: T) => T
>x : T
type T5 = { new <const T>(x: T): T };
>T5 : new <const T>(x: T) => T
>x : T
// Corrected repro from #51745
type Obj = { a: { b: { c: "123" } } };
>Obj : { a: { b: { c: "123"; };}; }
>a : { b: { c: "123";}; }
>b : { c: "123"; }
>c : "123"
type GetPath<T, P> =
>GetPath : GetPath<T, P>
P extends readonly [] ? T :
P extends readonly [infer A extends keyof T, ...infer Rest] ? GetPath<T[A], Rest> :
never;
function set<T, const P extends readonly string[]>(obj: T, path: P, value: GetPath<T, P>) {}
>set : <T, const P extends readonly string[]>(obj: T, path: P, value: GetPath<T, P>) => void
>obj : T
>path : P
>value : GetPath<T, P>
declare let obj: Obj;
>obj : Obj
declare let value: "123";
>value : "123"
set(obj, ['a', 'b', 'c'], value);
>set(obj, ['a', 'b', 'c'], value) : void
>set : <T, const P extends readonly string[]>(obj: T, path: P, value: GetPath<T, P>) => void
>obj : Obj
>['a', 'b', 'c'] : ["a", "b", "c"]
>'a' : "a"
>'b' : "b"
>'c' : "c"
>value : "123"
// Repro from #52007
declare function inners<const T extends readonly any[]>(...args: readonly [unknown, ...T, unknown]): T;
>inners : <const T extends readonly any[]>(...args: readonly [unknown, ...T, unknown]) => T
>args : readonly [unknown, ...T, unknown]
const test = inners(1,2,3,4,5);
>test : [2, 3, 4]
>inners(1,2,3,4,5) : [2, 3, 4]
>inners : <const T extends readonly any[]>(...args: readonly [unknown, ...T, unknown]) => T
>1 : 1
>2 : 2
>3 : 3
>4 : 4
>5 : 5
declare function inners2<const T extends readonly any[]>(args: readonly [unknown, ...T, unknown]): T;
>inners2 : <const T extends readonly any[]>(args: readonly [unknown, ...T, unknown]) => T
>args : readonly [unknown, ...T, unknown]
const test2 = inners2([1,2,3,4,5]);
>test2 : [2, 3, 4]
>inners2([1,2,3,4,5]) : [2, 3, 4]
>inners2 : <const T extends readonly any[]>(args: readonly [unknown, ...T, unknown]) => T
>[1,2,3,4,5] : [number, 2, 3, 4, number]
>1 : 1
>2 : 2
>3 : 3
>4 : 4
>5 : 5
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