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