196 lines
4 KiB
TypeScript
196 lines
4 KiB
TypeScript
//// [neverType.ts]
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function error(message: string): never {
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throw new Error(message);
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}
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function errorVoid(message: string) {
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throw new Error(message);
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}
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function fail() {
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return error("Something failed");
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}
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function failOrThrow(shouldFail: boolean) {
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if (shouldFail) {
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return fail();
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}
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throw new Error();
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}
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function infiniteLoop1() {
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while (true) {
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}
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}
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function infiniteLoop2(): never {
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while (true) {
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}
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}
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function move1(direction: "up" | "down") {
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switch (direction) {
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case "up":
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return 1;
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case "down":
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return -1;
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}
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return error("Should never get here");
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}
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function move2(direction: "up" | "down") {
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return direction === "up" ? 1 :
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direction === "down" ? -1 :
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error("Should never get here");
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}
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function check<T>(x: T | undefined) {
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return x || error("Undefined value");
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}
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class C {
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void1() {
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throw new Error();
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}
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void2() {
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while (true) {}
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}
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never1(): never {
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throw new Error();
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}
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never2(): never {
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while (true) {}
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}
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}
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function f1(x: string | number) {
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if (typeof x === "boolean") {
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x; // never
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}
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}
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function f2(x: string | number) {
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while (true) {
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if (typeof x === "boolean") {
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return x; // never
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}
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}
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}
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function test(cb: () => string) {
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let s = cb();
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return s;
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}
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let errorCallback = () => error("Error callback");
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test(() => "hello");
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test(() => fail());
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test(() => { throw new Error(); })
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test(errorCallback);
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//// [neverType.js]
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function error(message) {
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throw new Error(message);
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}
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function errorVoid(message) {
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throw new Error(message);
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}
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function fail() {
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return error("Something failed");
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}
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function failOrThrow(shouldFail) {
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if (shouldFail) {
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return fail();
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}
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throw new Error();
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}
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function infiniteLoop1() {
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while (true) {
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}
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}
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function infiniteLoop2() {
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while (true) {
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}
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}
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function move1(direction) {
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switch (direction) {
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case "up":
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return 1;
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case "down":
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return -1;
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}
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return error("Should never get here");
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}
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function move2(direction) {
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return direction === "up" ? 1 :
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direction === "down" ? -1 :
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error("Should never get here");
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}
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function check(x) {
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return x || error("Undefined value");
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}
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var C = (function () {
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function C() {
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}
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C.prototype.void1 = function () {
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throw new Error();
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};
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C.prototype.void2 = function () {
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while (true) { }
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};
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C.prototype.never1 = function () {
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throw new Error();
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};
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C.prototype.never2 = function () {
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while (true) { }
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};
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return C;
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}());
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function f1(x) {
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if (typeof x === "boolean") {
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x; // never
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}
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}
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function f2(x) {
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while (true) {
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if (typeof x === "boolean") {
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return x; // never
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}
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}
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}
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function test(cb) {
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var s = cb();
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return s;
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}
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var errorCallback = function () { return error("Error callback"); };
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test(function () { return "hello"; });
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test(function () { return fail(); });
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test(function () { throw new Error(); });
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test(errorCallback);
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//// [neverType.d.ts]
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declare function error(message: string): never;
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declare function errorVoid(message: string): void;
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declare function fail(): never;
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declare function failOrThrow(shouldFail: boolean): never;
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declare function infiniteLoop1(): void;
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declare function infiniteLoop2(): never;
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declare function move1(direction: "up" | "down"): number;
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declare function move2(direction: "up" | "down"): number;
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declare function check<T>(x: T | undefined): T;
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declare class C {
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void1(): void;
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void2(): void;
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never1(): never;
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never2(): never;
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}
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declare function f1(x: string | number): void;
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declare function f2(x: string | number): never;
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declare function test(cb: () => string): string;
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declare let errorCallback: () => never;
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