235 lines
8.7 KiB
Plaintext
235 lines
8.7 KiB
Plaintext
=== tests/cases/conformance/expressions/typeGuards/typeGuardsInRightOperandOfOrOrOperator.ts ===
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// In the right operand of a || operation,
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// the type of a variable or parameter is narrowed by any type guard in the left operand when false,
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// provided the right operand contains no assignments to the variable or parameter.
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function foo(x: number | string) {
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>foo : (x: string | number) => boolean
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>x : string | number
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return typeof x !== "string" || x.length === 10; // string
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>typeof x !== "string" || x.length === 10 : boolean
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>typeof x !== "string" : boolean
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>typeof x : string
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>x : string | number
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>"string" : string
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>x.length === 10 : boolean
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>x.length : number
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>x : string
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>length : number
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>10 : number
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}
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function foo2(x: number | string) {
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>foo2 : (x: string | number) => string | number | boolean
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>x : string | number
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// modify x in right hand operand
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return typeof x !== "string" || ((x = 10) || x); // string | number
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>typeof x !== "string" || ((x = 10) || x) : string | number | boolean
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>typeof x !== "string" : boolean
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>typeof x : string
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>x : string | number
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>"string" : string
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>((x = 10) || x) : string | number
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>(x = 10) || x : string | number
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>(x = 10) : number
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>x = 10 : number
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>x : string | number
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>10 : number
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>x : string | number
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}
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function foo3(x: number | string) {
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>foo3 : (x: string | number) => string | number | boolean
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>x : string | number
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// modify x in right hand operand with string type itself
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return typeof x !== "string" || ((x = "hello") || x); // string | number
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>typeof x !== "string" || ((x = "hello") || x) : string | number | boolean
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>typeof x !== "string" : boolean
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>typeof x : string
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>x : string | number
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>"string" : string
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>((x = "hello") || x) : string | number
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>(x = "hello") || x : string | number
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>(x = "hello") : string
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>x = "hello" : string
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>x : string | number
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>"hello" : string
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>x : string | number
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}
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function foo4(x: number | string | boolean) {
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>foo4 : (x: string | number | boolean) => boolean
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>x : string | number | boolean
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return typeof x === "string" // string | number | boolean
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>typeof x === "string" // string | number | boolean || typeof x === "number" // number | boolean || x : boolean
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>typeof x === "string" // string | number | boolean || typeof x === "number" : boolean
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>typeof x === "string" : boolean
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>typeof x : string
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>x : string | number | boolean
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>"string" : string
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|| typeof x === "number" // number | boolean
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>typeof x === "number" : boolean
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>typeof x : string
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>x : number | boolean
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>"number" : string
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|| x; // boolean
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>x : boolean
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}
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function foo5(x: number | string | boolean) {
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>foo5 : (x: string | number | boolean) => number | boolean
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>x : string | number | boolean
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// usage of x or assignment to separate variable shouldn't cause narrowing of type to stop
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var b: number | boolean;
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>b : number | boolean
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return typeof x === "string" // string | number | boolean
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>typeof x === "string" // string | number | boolean || ((b = x) || (typeof x === "number" // number | boolean || x)) : number | boolean
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>typeof x === "string" : boolean
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>typeof x : string
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>x : string | number | boolean
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>"string" : string
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|| ((b = x) || (typeof x === "number" // number | boolean
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>((b = x) || (typeof x === "number" // number | boolean || x)) : number | boolean
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>(b = x) || (typeof x === "number" // number | boolean || x) : number | boolean
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>(b = x) : number | boolean
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>b = x : number | boolean
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>b : number | boolean
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>x : number | boolean
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>(typeof x === "number" // number | boolean || x) : boolean
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>typeof x === "number" // number | boolean || x : boolean
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>typeof x === "number" : boolean
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>typeof x : string
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>x : number | boolean
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>"number" : string
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|| x)); // boolean
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>x : boolean
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}
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function foo6(x: number | string | boolean) {
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>foo6 : (x: string | number | boolean) => boolean
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>x : string | number | boolean
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// Mixing typeguard
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return typeof x === "string" // string | number | boolean
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>typeof x === "string" // string | number | boolean || (typeof x !== "number" // number | boolean ? x // boolean : x === 10) : boolean
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>typeof x === "string" : boolean
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>typeof x : string
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>x : string | number | boolean
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>"string" : string
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|| (typeof x !== "number" // number | boolean
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>(typeof x !== "number" // number | boolean ? x // boolean : x === 10) : boolean
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>typeof x !== "number" // number | boolean ? x // boolean : x === 10 : boolean
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>typeof x !== "number" : boolean
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>typeof x : string
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>x : number | boolean
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>"number" : string
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? x // boolean
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>x : boolean
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: x === 10) // number
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>x === 10 : boolean
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>x : number
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>10 : number
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}
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function foo7(x: number | string | boolean) {
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>foo7 : (x: string | number | boolean) => string | number | boolean
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>x : string | number | boolean
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var y: number| boolean | string;
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>y : string | number | boolean
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var z: number| boolean | string;
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>z : string | number | boolean
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// Mixing typeguard narrowing
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// Assigning value to x deep inside another guard stops narrowing of type too
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return typeof x === "string"
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>typeof x === "string" || ((z = x) // string | number | boolean - x changed deeper in conditional expression || (typeof x === "number" // change value of x ? (x = 10 && x.toString()) // number | boolean | string // do not change value : (y = x && x.toString()))) : string | number | boolean
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>typeof x === "string" : boolean
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>typeof x : string
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>x : string | number | boolean
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>"string" : string
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|| ((z = x) // string | number | boolean - x changed deeper in conditional expression
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>((z = x) // string | number | boolean - x changed deeper in conditional expression || (typeof x === "number" // change value of x ? (x = 10 && x.toString()) // number | boolean | string // do not change value : (y = x && x.toString()))) : string | number | boolean
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>(z = x) // string | number | boolean - x changed deeper in conditional expression || (typeof x === "number" // change value of x ? (x = 10 && x.toString()) // number | boolean | string // do not change value : (y = x && x.toString())) : string | number | boolean
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>(z = x) : string | number | boolean
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>z = x : string | number | boolean
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>z : string | number | boolean
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>x : string | number | boolean
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|| (typeof x === "number"
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>(typeof x === "number" // change value of x ? (x = 10 && x.toString()) // number | boolean | string // do not change value : (y = x && x.toString())) : string
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>typeof x === "number" // change value of x ? (x = 10 && x.toString()) // number | boolean | string // do not change value : (y = x && x.toString()) : string
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>typeof x === "number" : boolean
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>typeof x : string
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>x : string | number | boolean
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>"number" : string
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// change value of x
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? (x = 10 && x.toString()) // number | boolean | string
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>(x = 10 && x.toString()) : string
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>x = 10 && x.toString() : string
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>x : string | number | boolean
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>10 && x.toString() : string
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>10 : number
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>x.toString() : string
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>x.toString : () => string
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>x : string | number | boolean
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>toString : () => string
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// do not change value
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: (y = x && x.toString()))); // number | boolean | string
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>(y = x && x.toString()) : string
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>y = x && x.toString() : string
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>y : string | number | boolean
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>x && x.toString() : string
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>x : string | number | boolean
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>x.toString() : string
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>x.toString : () => string
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>x : string | number | boolean
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>toString : () => string
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}
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function foo8(x: number | string) {
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>foo8 : (x: string | number) => number | boolean
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>x : string | number
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// Mixing typeguard
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// Assigning value to x in outer guard shouldn't stop narrowing in the inner expression
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return typeof x === "string"
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>typeof x === "string" || (x = 10) // change x - number| string || (typeof x === "number" ? x // number : x.length) : number | boolean
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>typeof x === "string" || (x = 10) : number | boolean
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>typeof x === "string" : boolean
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>typeof x : string
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>x : string | number
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>"string" : string
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|| (x = 10) // change x - number| string
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>(x = 10) : number
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>x = 10 : number
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>x : string | number
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>10 : number
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|| (typeof x === "number"
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>(typeof x === "number" ? x // number : x.length) : number
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>typeof x === "number" ? x // number : x.length : number
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>typeof x === "number" : boolean
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>typeof x : string
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>x : string | number
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>"number" : string
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? x // number
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>x : number
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: x.length); // string
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>x.length : number
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>x : string
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>length : number
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}
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