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tests/cases/compiler/narrowByEquality.ts(41,5): error TS2839: This condition will always return 'false' since JavaScript compares objects by reference, not value.
tests/cases/compiler/narrowByEquality.ts(54,15): error TS2322: Type 'string | number' is not assignable to type 'number'.
Type 'string' is not assignable to type 'number'.
tests/cases/compiler/narrowByEquality.ts(55,9): error TS2322: Type 'string | number' is not assignable to type 'number'.
Type 'string' is not assignable to type 'number'.
==== tests/cases/compiler/narrowByEquality.ts (3 errors) ====
declare let x: number | string | boolean
declare let n: number;
declare let s: string;
declare let b: boolean;
declare let xUnknown: unknown;
if (x == n) {
x;
}
if (x == s) {
x;
}
if (x == b) {
x;
}
if (x == 1) {
x;
}
if (x == "") {
x;
}
if (x == "foo") {
x;
}
if (x == true) {
x;
}
if (x == false) {
x;
}
declare let xAndObj: number | string | boolean | object
if (xAndObj == {}) {
~~~~~~~~~~~~~
!!! error TS2839: This condition will always return 'false' since JavaScript compares objects by reference, not value.
xAndObj;
}
if (x == xAndObj) {
x;
xAndObj;
}
// Repro from #24991
function test(level: number | string):number {
if (level == +level) {
const q2: number = level; // error
~~
!!! error TS2322: Type 'string | number' is not assignable to type 'number'.
!!! error TS2322: Type 'string' is not assignable to type 'number'.
return level;
~~~~~~~~~~~~~
!!! error TS2322: Type 'string | number' is not assignable to type 'number'.
!!! error TS2322: Type 'string' is not assignable to type 'number'.
}
return 0;
}
// From issue #32798
if (xUnknown == null) {
xUnknown;
} else {
xUnknown
}
if (xUnknown != null) {
xUnknown;
} else {
xUnknown;
}
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