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=== tests/cases/conformance/expressions/typeGuards/typeGuardsInRightOperandOfAndAndOperator.ts ===
// In the right operand of a && operation,
// the type of a variable or parameter is narrowed by any type guard in the left operand when true.
function foo(x: number | string) {
>foo : Symbol(foo, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 0, 0))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 2, 13))
return typeof x === "string" && x.length === 10; // string
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 2, 13))
>x.length : Symbol(String.length, Decl(lib.d.ts, --, --))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 2, 13))
>length : Symbol(String.length, Decl(lib.d.ts, --, --))
}
function foo2(x: number | string) {
>foo2 : Symbol(foo2, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 4, 1))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 5, 14))
// modify x in right hand operand
return typeof x === "string" && ((x = 10) && x); // string | number
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 5, 14))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 5, 14))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 5, 14))
}
function foo3(x: number | string) {
>foo3 : Symbol(foo3, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 8, 1))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 9, 14))
// modify x in right hand operand with string type itself
return typeof x === "string" && ((x = "hello") && x); // string | number
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 9, 14))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 9, 14))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 9, 14))
}
function foo4(x: number | string | boolean) {
>foo4 : Symbol(foo4, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 12, 1))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 13, 14))
return typeof x !== "string" // string | number | boolean
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 13, 14))
&& typeof x !== "number" // number | boolean
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 13, 14))
&& x; // boolean
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 13, 14))
}
function foo5(x: number | string | boolean) {
>foo5 : Symbol(foo5, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 17, 1))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 18, 14))
// usage of x or assignment to separate variable shouldn't cause narrowing of type to stop
var b: number | boolean;
>b : Symbol(b, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 20, 7))
return typeof x !== "string" // string | number | boolean
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 18, 14))
&& ((b = x) && (typeof x !== "number" // number | boolean
>b : Symbol(b, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 20, 7))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 18, 14))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 18, 14))
&& x)); // boolean
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 18, 14))
}
function foo6(x: number | string | boolean) {
>foo6 : Symbol(foo6, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 24, 1))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 25, 14))
// Mixing typeguard narrowing in if statement with conditional expression typeguard
return typeof x !== "string" // string | number | boolean
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 25, 14))
&& (typeof x !== "number" // number | boolean
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 25, 14))
? x // boolean
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 25, 14))
: x === 10) // number
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 25, 14))
}
function foo7(x: number | string | boolean) {
>foo7 : Symbol(foo7, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 31, 1))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 32, 14))
var y: number| boolean | string;
>y : Symbol(y, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 33, 7))
var z: number| boolean | string;
>z : Symbol(z, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 34, 7))
// Mixing typeguard narrowing
return typeof x !== "string"
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 32, 14))
&& ((z = x) // number | boolean
>z : Symbol(z, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 34, 7))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 32, 14))
&& (typeof x === "number"
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 32, 14))
// change value of x
? ((x = 10) && x.toString()) // x is number
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 32, 14))
>x.toString : Symbol(Number.toString, Decl(lib.d.ts, --, --))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 32, 14))
>toString : Symbol(Number.toString, Decl(lib.d.ts, --, --))
// do not change value
: ((y = x) && x.toString()))); // x is boolean
>y : Symbol(y, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 33, 7))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 32, 14))
>x.toString : Symbol(Object.toString, Decl(lib.d.ts, --, --))
>x : Symbol(x, Decl(typeGuardsInRightOperandOfAndAndOperator.ts, 32, 14))
>toString : Symbol(Object.toString, Decl(lib.d.ts, --, --))
}
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