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