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Add [Constructor]Parameters types to lib.d.ts #26243

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Aug 31, 2018
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Add [Constructor]Parameters types to lib.d.ts #26243

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10 changes: 10 additions & 0 deletions src/lib/es5.d.ts
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Expand Up @@ -1378,6 +1378,16 @@ type Extract<T, U> = T extends U ? T : never;
*/
type NonNullable<T> = T extends null | undefined ? never : T;

/**
* Obtain the parameters of a function type in a tuple
*/
type Parameters<T extends (...args: any[]) => any> = T extends (...args: infer P) => any ? P : never;

/**
* Obtain the parameters of a constructor function type in a tuple
*/
type ConstructorParameters<T extends new (...args: any[]) => any> = T extends new (...args: infer P) => any ? P : never;

/**
* Obtain the return type of a function type
*/
Expand Down
25 changes: 17 additions & 8 deletions tests/baselines/reference/genericRestParameters1.errors.txt
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@@ -1,11 +1,15 @@
tests/cases/conformance/types/rest/genericRestParameters1.ts(22,1): error TS2556: Expected 3 arguments, but got 1 or more.
tests/cases/conformance/types/rest/genericRestParameters1.ts(31,1): error TS2556: Expected 3 arguments, but got 1 or more.
tests/cases/conformance/types/rest/genericRestParameters1.ts(166,1): error TS2322: Type '(a: never) => void' is not assignable to type '(...args: any[]) => void'.
tests/cases/conformance/types/rest/genericRestParameters1.ts(133,40): error TS2344: Type '(...args: T) => void' does not satisfy the constraint '(...args: any[]) => any'.
tests/cases/conformance/types/rest/genericRestParameters1.ts(134,51): error TS2344: Type 'new (...args: T) => void' does not satisfy the constraint 'new (...args: any[]) => any'.
tests/cases/conformance/types/rest/genericRestParameters1.ts(135,23): error TS2344: Type 'Function' does not satisfy the constraint '(...args: any[]) => any'.
Type 'Function' provides no match for the signature '(...args: any[]): any'.
tests/cases/conformance/types/rest/genericRestParameters1.ts(164,1): error TS2322: Type '(a: never) => void' is not assignable to type '(...args: any[]) => void'.
Types of parameters 'a' and 'args' are incompatible.
Type 'any' is not assignable to type 'never'.


==== tests/cases/conformance/types/rest/genericRestParameters1.ts (3 errors) ====
==== tests/cases/conformance/types/rest/genericRestParameters1.ts (6 errors) ====
declare let f1: (...x: [number, string, boolean]) => void;
declare let f2: (x0: number, x1: string, x2: boolean) => void;

Expand Down Expand Up @@ -136,17 +140,22 @@ tests/cases/conformance/types/rest/genericRestParameters1.ts(166,1): error TS232

const c30 = f30(42, x => "" + x, x => x + 1); // [(x: number) => string, (x: number) => number]

type Parameters<T extends Function> = T extends ((...args: infer U) => any) | (new(...args: infer U) => any) ? U : any[];

type T01 = Parameters<(x: number, y: string, z: boolean) => void>;
type T02 = Parameters<(...args: [number, string, boolean]) => void>;
type T03 = Parameters<new (x: number, y: string, z: boolean) => void>;
type T04 = Parameters<new (...args: [number, string, boolean]) => void>;
type T03 = ConstructorParameters<new (x: number, y: string, z: boolean) => void>;
type T04 = ConstructorParameters<new (...args: [number, string, boolean]) => void>;
type T05<T> = Parameters<(...args: T[]) => void>;
type T06<T> = Parameters<new (...args: []) => void>;
type T06<T> = ConstructorParameters<new (...args: []) => void>;
type T07<T extends any[]> = Parameters<(...args: T) => void>;
type T08<T extends any[]> = Parameters<new (...args: T) => void>;
~~~~~~~~~~~~~~~~~~~~
!!! error TS2344: Type '(...args: T) => void' does not satisfy the constraint '(...args: any[]) => any'.
type T08<T extends any[]> = ConstructorParameters<new (...args: T) => void>;
~~~~~~~~~~~~~~~~~~~~~~~~
!!! error TS2344: Type 'new (...args: T) => void' does not satisfy the constraint 'new (...args: any[]) => any'.
type T09 = Parameters<Function>;
~~~~~~~~
!!! error TS2344: Type 'Function' does not satisfy the constraint '(...args: any[]) => any'.
!!! error TS2344: Type 'Function' provides no match for the signature '(...args: any[]): any'.

type Record1 = {
move: [number, 'left' | 'right'];
Expand Down
19 changes: 8 additions & 11 deletions tests/baselines/reference/genericRestParameters1.js
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Expand Up @@ -125,16 +125,14 @@ declare function f30<T, U extends ((x: T) => any)[]>(x: T, ...args: U): U;

const c30 = f30(42, x => "" + x, x => x + 1); // [(x: number) => string, (x: number) => number]

type Parameters<T extends Function> = T extends ((...args: infer U) => any) | (new(...args: infer U) => any) ? U : any[];

type T01 = Parameters<(x: number, y: string, z: boolean) => void>;
type T02 = Parameters<(...args: [number, string, boolean]) => void>;
type T03 = Parameters<new (x: number, y: string, z: boolean) => void>;
type T04 = Parameters<new (...args: [number, string, boolean]) => void>;
type T03 = ConstructorParameters<new (x: number, y: string, z: boolean) => void>;
type T04 = ConstructorParameters<new (...args: [number, string, boolean]) => void>;
type T05<T> = Parameters<(...args: T[]) => void>;
type T06<T> = Parameters<new (...args: []) => void>;
type T06<T> = ConstructorParameters<new (...args: []) => void>;
type T07<T extends any[]> = Parameters<(...args: T) => void>;
type T08<T extends any[]> = Parameters<new (...args: T) => void>;
type T08<T extends any[]> = ConstructorParameters<new (...args: T) => void>;
type T09 = Parameters<Function>;

type Record1 = {
Expand Down Expand Up @@ -327,15 +325,14 @@ declare const g22: (z?: boolean | undefined) => string[];
declare const g23: () => string[];
declare function f30<T, U extends ((x: T) => any)[]>(x: T, ...args: U): U;
declare const c30: [(x: number) => string, (x: number) => number];
declare type Parameters<T extends Function> = T extends ((...args: infer U) => any) | (new (...args: infer U) => any) ? U : any[];
declare type T01 = Parameters<(x: number, y: string, z: boolean) => void>;
declare type T02 = Parameters<(...args: [number, string, boolean]) => void>;
declare type T03 = Parameters<new (x: number, y: string, z: boolean) => void>;
declare type T04 = Parameters<new (...args: [number, string, boolean]) => void>;
declare type T03 = ConstructorParameters<new (x: number, y: string, z: boolean) => void>;
declare type T04 = ConstructorParameters<new (...args: [number, string, boolean]) => void>;
declare type T05<T> = Parameters<(...args: T[]) => void>;
declare type T06<T> = Parameters<new (...args: []) => void>;
declare type T06<T> = ConstructorParameters<new (...args: []) => void>;
declare type T07<T extends any[]> = Parameters<(...args: T) => void>;
declare type T08<T extends any[]> = Parameters<new (...args: T) => void>;
declare type T08<T extends any[]> = ConstructorParameters<new (...args: T) => void>;
declare type T09 = Parameters<Function>;
declare type Record1 = {
move: [number, 'left' | 'right'];
Expand Down
193 changes: 91 additions & 102 deletions tests/baselines/reference/genericRestParameters1.symbols
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Expand Up @@ -494,160 +494,149 @@ const c30 = f30(42, x => "" + x, x => x + 1); // [(x: number) => string, (x: nu
>x : Symbol(x, Decl(genericRestParameters1.ts, 124, 32))
>x : Symbol(x, Decl(genericRestParameters1.ts, 124, 32))

type Parameters<T extends Function> = T extends ((...args: infer U) => any) | (new(...args: infer U) => any) ? U : any[];
>Parameters : Symbol(Parameters, Decl(genericRestParameters1.ts, 124, 45))
>T : Symbol(T, Decl(genericRestParameters1.ts, 126, 16))
>Function : Symbol(Function, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))
>T : Symbol(T, Decl(genericRestParameters1.ts, 126, 16))
>args : Symbol(args, Decl(genericRestParameters1.ts, 126, 50))
>U : Symbol(U, Decl(genericRestParameters1.ts, 126, 64), Decl(genericRestParameters1.ts, 126, 97))
>args : Symbol(args, Decl(genericRestParameters1.ts, 126, 83))
>U : Symbol(U, Decl(genericRestParameters1.ts, 126, 64), Decl(genericRestParameters1.ts, 126, 97))
>U : Symbol(U, Decl(genericRestParameters1.ts, 126, 64), Decl(genericRestParameters1.ts, 126, 97))

type T01 = Parameters<(x: number, y: string, z: boolean) => void>;
>T01 : Symbol(T01, Decl(genericRestParameters1.ts, 126, 121))
>Parameters : Symbol(Parameters, Decl(genericRestParameters1.ts, 124, 45))
>x : Symbol(x, Decl(genericRestParameters1.ts, 128, 23))
>y : Symbol(y, Decl(genericRestParameters1.ts, 128, 33))
>z : Symbol(z, Decl(genericRestParameters1.ts, 128, 44))
>T01 : Symbol(T01, Decl(genericRestParameters1.ts, 124, 45))
>Parameters : Symbol(Parameters, Decl(lib.es5.d.ts, --, --))
>x : Symbol(x, Decl(genericRestParameters1.ts, 126, 23))
>y : Symbol(y, Decl(genericRestParameters1.ts, 126, 33))
>z : Symbol(z, Decl(genericRestParameters1.ts, 126, 44))

type T02 = Parameters<(...args: [number, string, boolean]) => void>;
>T02 : Symbol(T02, Decl(genericRestParameters1.ts, 128, 66))
>Parameters : Symbol(Parameters, Decl(genericRestParameters1.ts, 124, 45))
>args : Symbol(args, Decl(genericRestParameters1.ts, 129, 23))

type T03 = Parameters<new (x: number, y: string, z: boolean) => void>;
>T03 : Symbol(T03, Decl(genericRestParameters1.ts, 129, 68))
>Parameters : Symbol(Parameters, Decl(genericRestParameters1.ts, 124, 45))
>x : Symbol(x, Decl(genericRestParameters1.ts, 130, 27))
>y : Symbol(y, Decl(genericRestParameters1.ts, 130, 37))
>z : Symbol(z, Decl(genericRestParameters1.ts, 130, 48))

type T04 = Parameters<new (...args: [number, string, boolean]) => void>;
>T04 : Symbol(T04, Decl(genericRestParameters1.ts, 130, 70))
>Parameters : Symbol(Parameters, Decl(genericRestParameters1.ts, 124, 45))
>args : Symbol(args, Decl(genericRestParameters1.ts, 131, 27))
>T02 : Symbol(T02, Decl(genericRestParameters1.ts, 126, 66))
>Parameters : Symbol(Parameters, Decl(lib.es5.d.ts, --, --))
>args : Symbol(args, Decl(genericRestParameters1.ts, 127, 23))

type T03 = ConstructorParameters<new (x: number, y: string, z: boolean) => void>;
>T03 : Symbol(T03, Decl(genericRestParameters1.ts, 127, 68))
>ConstructorParameters : Symbol(ConstructorParameters, Decl(lib.es5.d.ts, --, --))
>x : Symbol(x, Decl(genericRestParameters1.ts, 128, 38))
>y : Symbol(y, Decl(genericRestParameters1.ts, 128, 48))
>z : Symbol(z, Decl(genericRestParameters1.ts, 128, 59))

type T04 = ConstructorParameters<new (...args: [number, string, boolean]) => void>;
>T04 : Symbol(T04, Decl(genericRestParameters1.ts, 128, 81))
>ConstructorParameters : Symbol(ConstructorParameters, Decl(lib.es5.d.ts, --, --))
>args : Symbol(args, Decl(genericRestParameters1.ts, 129, 38))

type T05<T> = Parameters<(...args: T[]) => void>;
>T05 : Symbol(T05, Decl(genericRestParameters1.ts, 131, 72))
>T05 : Symbol(T05, Decl(genericRestParameters1.ts, 129, 83))
>T : Symbol(T, Decl(genericRestParameters1.ts, 130, 9))
>Parameters : Symbol(Parameters, Decl(lib.es5.d.ts, --, --))
>args : Symbol(args, Decl(genericRestParameters1.ts, 130, 26))
>T : Symbol(T, Decl(genericRestParameters1.ts, 130, 9))

type T06<T> = ConstructorParameters<new (...args: []) => void>;
>T06 : Symbol(T06, Decl(genericRestParameters1.ts, 130, 49))
>T : Symbol(T, Decl(genericRestParameters1.ts, 131, 9))
>ConstructorParameters : Symbol(ConstructorParameters, Decl(lib.es5.d.ts, --, --))
>args : Symbol(args, Decl(genericRestParameters1.ts, 131, 41))

type T07<T extends any[]> = Parameters<(...args: T) => void>;
>T07 : Symbol(T07, Decl(genericRestParameters1.ts, 131, 63))
>T : Symbol(T, Decl(genericRestParameters1.ts, 132, 9))
>Parameters : Symbol(Parameters, Decl(genericRestParameters1.ts, 124, 45))
>args : Symbol(args, Decl(genericRestParameters1.ts, 132, 26))
>Parameters : Symbol(Parameters, Decl(lib.es5.d.ts, --, --))
>args : Symbol(args, Decl(genericRestParameters1.ts, 132, 40))
>T : Symbol(T, Decl(genericRestParameters1.ts, 132, 9))

type T06<T> = Parameters<new (...args: []) => void>;
>T06 : Symbol(T06, Decl(genericRestParameters1.ts, 132, 49))
type T08<T extends any[]> = ConstructorParameters<new (...args: T) => void>;
>T08 : Symbol(T08, Decl(genericRestParameters1.ts, 132, 61))
>T : Symbol(T, Decl(genericRestParameters1.ts, 133, 9))
>ConstructorParameters : Symbol(ConstructorParameters, Decl(lib.es5.d.ts, --, --))
>args : Symbol(args, Decl(genericRestParameters1.ts, 133, 55))
>T : Symbol(T, Decl(genericRestParameters1.ts, 133, 9))
>Parameters : Symbol(Parameters, Decl(genericRestParameters1.ts, 124, 45))
>args : Symbol(args, Decl(genericRestParameters1.ts, 133, 30))

type T07<T extends any[]> = Parameters<(...args: T) => void>;
>T07 : Symbol(T07, Decl(genericRestParameters1.ts, 133, 52))
>T : Symbol(T, Decl(genericRestParameters1.ts, 134, 9))
>Parameters : Symbol(Parameters, Decl(genericRestParameters1.ts, 124, 45))
>args : Symbol(args, Decl(genericRestParameters1.ts, 134, 40))
>T : Symbol(T, Decl(genericRestParameters1.ts, 134, 9))

type T08<T extends any[]> = Parameters<new (...args: T) => void>;
>T08 : Symbol(T08, Decl(genericRestParameters1.ts, 134, 61))
>T : Symbol(T, Decl(genericRestParameters1.ts, 135, 9))
>Parameters : Symbol(Parameters, Decl(genericRestParameters1.ts, 124, 45))
>args : Symbol(args, Decl(genericRestParameters1.ts, 135, 44))
>T : Symbol(T, Decl(genericRestParameters1.ts, 135, 9))

type T09 = Parameters<Function>;
>T09 : Symbol(T09, Decl(genericRestParameters1.ts, 135, 65))
>Parameters : Symbol(Parameters, Decl(genericRestParameters1.ts, 124, 45))
>T09 : Symbol(T09, Decl(genericRestParameters1.ts, 133, 76))
>Parameters : Symbol(Parameters, Decl(lib.es5.d.ts, --, --))
>Function : Symbol(Function, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))

type Record1 = {
>Record1 : Symbol(Record1, Decl(genericRestParameters1.ts, 136, 32))
>Record1 : Symbol(Record1, Decl(genericRestParameters1.ts, 134, 32))

move: [number, 'left' | 'right'];
>move : Symbol(move, Decl(genericRestParameters1.ts, 138, 16))
>move : Symbol(move, Decl(genericRestParameters1.ts, 136, 16))

jump: [number, 'up' | 'down'];
>jump : Symbol(jump, Decl(genericRestParameters1.ts, 139, 35))
>jump : Symbol(jump, Decl(genericRestParameters1.ts, 137, 35))

stop: string;
>stop : Symbol(stop, Decl(genericRestParameters1.ts, 140, 32))
>stop : Symbol(stop, Decl(genericRestParameters1.ts, 138, 32))

done: [];
>done : Symbol(done, Decl(genericRestParameters1.ts, 141, 15))
>done : Symbol(done, Decl(genericRestParameters1.ts, 139, 15))
}

type EventType<T> = {
>EventType : Symbol(EventType, Decl(genericRestParameters1.ts, 143, 1))
>T : Symbol(T, Decl(genericRestParameters1.ts, 145, 15))
>EventType : Symbol(EventType, Decl(genericRestParameters1.ts, 141, 1))
>T : Symbol(T, Decl(genericRestParameters1.ts, 143, 15))

emit<K extends keyof T = keyof T>(e: K, ...payload: T[K] extends any[] ? T[K] : [T[K]]): void;
>emit : Symbol(emit, Decl(genericRestParameters1.ts, 145, 21))
>K : Symbol(K, Decl(genericRestParameters1.ts, 146, 7))
>T : Symbol(T, Decl(genericRestParameters1.ts, 145, 15))
>T : Symbol(T, Decl(genericRestParameters1.ts, 145, 15))
>e : Symbol(e, Decl(genericRestParameters1.ts, 146, 36))
>K : Symbol(K, Decl(genericRestParameters1.ts, 146, 7))
>payload : Symbol(payload, Decl(genericRestParameters1.ts, 146, 41))
>T : Symbol(T, Decl(genericRestParameters1.ts, 145, 15))
>K : Symbol(K, Decl(genericRestParameters1.ts, 146, 7))
>T : Symbol(T, Decl(genericRestParameters1.ts, 145, 15))
>K : Symbol(K, Decl(genericRestParameters1.ts, 146, 7))
>T : Symbol(T, Decl(genericRestParameters1.ts, 145, 15))
>K : Symbol(K, Decl(genericRestParameters1.ts, 146, 7))
>emit : Symbol(emit, Decl(genericRestParameters1.ts, 143, 21))
>K : Symbol(K, Decl(genericRestParameters1.ts, 144, 7))
>T : Symbol(T, Decl(genericRestParameters1.ts, 143, 15))
>T : Symbol(T, Decl(genericRestParameters1.ts, 143, 15))
>e : Symbol(e, Decl(genericRestParameters1.ts, 144, 36))
>K : Symbol(K, Decl(genericRestParameters1.ts, 144, 7))
>payload : Symbol(payload, Decl(genericRestParameters1.ts, 144, 41))
>T : Symbol(T, Decl(genericRestParameters1.ts, 143, 15))
>K : Symbol(K, Decl(genericRestParameters1.ts, 144, 7))
>T : Symbol(T, Decl(genericRestParameters1.ts, 143, 15))
>K : Symbol(K, Decl(genericRestParameters1.ts, 144, 7))
>T : Symbol(T, Decl(genericRestParameters1.ts, 143, 15))
>K : Symbol(K, Decl(genericRestParameters1.ts, 144, 7))
}

declare var events: EventType<Record1>;
>events : Symbol(events, Decl(genericRestParameters1.ts, 149, 11))
>EventType : Symbol(EventType, Decl(genericRestParameters1.ts, 143, 1))
>Record1 : Symbol(Record1, Decl(genericRestParameters1.ts, 136, 32))
>events : Symbol(events, Decl(genericRestParameters1.ts, 147, 11))
>EventType : Symbol(EventType, Decl(genericRestParameters1.ts, 141, 1))
>Record1 : Symbol(Record1, Decl(genericRestParameters1.ts, 134, 32))

events.emit('move', 10, 'left');
>events.emit : Symbol(emit, Decl(genericRestParameters1.ts, 145, 21))
>events : Symbol(events, Decl(genericRestParameters1.ts, 149, 11))
>emit : Symbol(emit, Decl(genericRestParameters1.ts, 145, 21))
>events.emit : Symbol(emit, Decl(genericRestParameters1.ts, 143, 21))
>events : Symbol(events, Decl(genericRestParameters1.ts, 147, 11))
>emit : Symbol(emit, Decl(genericRestParameters1.ts, 143, 21))

events.emit('jump', 20, 'up');
>events.emit : Symbol(emit, Decl(genericRestParameters1.ts, 145, 21))
>events : Symbol(events, Decl(genericRestParameters1.ts, 149, 11))
>emit : Symbol(emit, Decl(genericRestParameters1.ts, 145, 21))
>events.emit : Symbol(emit, Decl(genericRestParameters1.ts, 143, 21))
>events : Symbol(events, Decl(genericRestParameters1.ts, 147, 11))
>emit : Symbol(emit, Decl(genericRestParameters1.ts, 143, 21))

events.emit('stop', 'Bye!');
>events.emit : Symbol(emit, Decl(genericRestParameters1.ts, 145, 21))
>events : Symbol(events, Decl(genericRestParameters1.ts, 149, 11))
>emit : Symbol(emit, Decl(genericRestParameters1.ts, 145, 21))
>events.emit : Symbol(emit, Decl(genericRestParameters1.ts, 143, 21))
>events : Symbol(events, Decl(genericRestParameters1.ts, 147, 11))
>emit : Symbol(emit, Decl(genericRestParameters1.ts, 143, 21))

events.emit('done');
>events.emit : Symbol(emit, Decl(genericRestParameters1.ts, 145, 21))
>events : Symbol(events, Decl(genericRestParameters1.ts, 149, 11))
>emit : Symbol(emit, Decl(genericRestParameters1.ts, 145, 21))
>events.emit : Symbol(emit, Decl(genericRestParameters1.ts, 143, 21))
>events : Symbol(events, Decl(genericRestParameters1.ts, 147, 11))
>emit : Symbol(emit, Decl(genericRestParameters1.ts, 143, 21))

// Repro from #25871

declare var ff1: (... args: any[]) => void;
>ff1 : Symbol(ff1, Decl(genericRestParameters1.ts, 157, 11))
>args : Symbol(args, Decl(genericRestParameters1.ts, 157, 18))
>ff1 : Symbol(ff1, Decl(genericRestParameters1.ts, 155, 11))
>args : Symbol(args, Decl(genericRestParameters1.ts, 155, 18))

declare var ff2: () => void;
>ff2 : Symbol(ff2, Decl(genericRestParameters1.ts, 159, 11))
>ff2 : Symbol(ff2, Decl(genericRestParameters1.ts, 157, 11))

declare var ff3: (...args: []) => void;
>ff3 : Symbol(ff3, Decl(genericRestParameters1.ts, 160, 11))
>args : Symbol(args, Decl(genericRestParameters1.ts, 160, 18))
>ff3 : Symbol(ff3, Decl(genericRestParameters1.ts, 158, 11))
>args : Symbol(args, Decl(genericRestParameters1.ts, 158, 18))

declare var ff4: (a: never) => void;
>ff4 : Symbol(ff4, Decl(genericRestParameters1.ts, 161, 11))
>a : Symbol(a, Decl(genericRestParameters1.ts, 161, 18))
>ff4 : Symbol(ff4, Decl(genericRestParameters1.ts, 159, 11))
>a : Symbol(a, Decl(genericRestParameters1.ts, 159, 18))

ff1 = ff2;
>ff1 : Symbol(ff1, Decl(genericRestParameters1.ts, 157, 11))
>ff2 : Symbol(ff2, Decl(genericRestParameters1.ts, 159, 11))
>ff1 : Symbol(ff1, Decl(genericRestParameters1.ts, 155, 11))
>ff2 : Symbol(ff2, Decl(genericRestParameters1.ts, 157, 11))

ff1 = ff3;
>ff1 : Symbol(ff1, Decl(genericRestParameters1.ts, 157, 11))
>ff3 : Symbol(ff3, Decl(genericRestParameters1.ts, 160, 11))
>ff1 : Symbol(ff1, Decl(genericRestParameters1.ts, 155, 11))
>ff3 : Symbol(ff3, Decl(genericRestParameters1.ts, 158, 11))

ff1 = ff4; // Error
>ff1 : Symbol(ff1, Decl(genericRestParameters1.ts, 157, 11))
>ff4 : Symbol(ff4, Decl(genericRestParameters1.ts, 161, 11))
>ff1 : Symbol(ff1, Decl(genericRestParameters1.ts, 155, 11))
>ff4 : Symbol(ff4, Decl(genericRestParameters1.ts, 159, 11))