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controlFlowTruthiness.types
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controlFlowTruthiness.types
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=== tests/cases/conformance/controlFlow/controlFlowTruthiness.ts ===
declare function foo(): string | undefined;
>foo : () => string | undefined
function f1() {
>f1 : () => void
let x = foo();
>x : string | undefined
>foo() : string | undefined
>foo : () => string | undefined
if (x) {
>x : string | undefined
x; // string
>x : string
}
else {
x; // string | undefined
>x : string | undefined
}
}
function f2() {
>f2 : () => void
let x: string | undefined;
>x : string | undefined
x = foo();
>x = foo() : string | undefined
>x : string | undefined
>foo() : string | undefined
>foo : () => string | undefined
if (x) {
>x : string | undefined
x; // string
>x : string
}
else {
x; // string | undefined
>x : string | undefined
}
}
function f3() {
>f3 : () => void
let x: string | undefined;
>x : string | undefined
if (x = foo()) {
>x = foo() : string | undefined
>x : string | undefined
>foo() : string | undefined
>foo : () => string | undefined
x; // string
>x : string
}
else {
x; // string | undefined
>x : string | undefined
}
}
function f4() {
>f4 : () => void
let x: string | undefined;
>x : string | undefined
if (!(x = foo())) {
>!(x = foo()) : boolean
>(x = foo()) : string | undefined
>x = foo() : string | undefined
>x : string | undefined
>foo() : string | undefined
>foo : () => string | undefined
x; // string | undefined
>x : string | undefined
}
else {
x; // string
>x : string
}
}
function f5() {
>f5 : () => void
let x: string | undefined;
>x : string | undefined
let y: string | undefined;
>y : string | undefined
if (x = y = foo()) {
>x = y = foo() : string | undefined
>x : string | undefined
>y = foo() : string | undefined
>y : string | undefined
>foo() : string | undefined
>foo : () => string | undefined
x; // string
>x : string
y; // string | undefined
>y : string
}
else {
x; // string | undefined
>x : string | undefined
y; // string | undefined
>y : string | undefined
}
}
function f6() {
>f6 : () => void
let x: string | undefined;
>x : string | undefined
let y: string | undefined;
>y : string | undefined
if (x = foo(), y = foo()) {
>x = foo(), y = foo() : string | undefined
>x = foo() : string | undefined
>x : string | undefined
>foo() : string | undefined
>foo : () => string | undefined
>y = foo() : string | undefined
>y : string | undefined
>foo() : string | undefined
>foo : () => string | undefined
x; // string | undefined
>x : string | undefined
y; // string
>y : string
}
else {
x; // string | undefined
>x : string | undefined
y; // string | undefined
>y : string | undefined
}
}
function f7(x: {}) {
>f7 : (x: {}) => void
>x : {}
if (x) {
>x : {}
x; // {}
>x : {}
}
else {
x; // {}
>x : {}
}
}
function f8<T>(x: T) {
>f8 : <T>(x: T) => void
>x : T
if (x) {
>x : T
x; // {}
>x : T
}
else {
x; // {}
>x : T
}
}
function f9<T extends object>(x: T) {
>f9 : <T extends object>(x: T) => void
>x : T
if (x) {
>x : T
x; // {}
>x : T
}
else {
x; // never
>x : never
}
}