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=== tests/cases/compiler/arrayFind.ts ===
// test fix for #18112, type guard predicates should narrow returned element
function isNumber(x: any): x is number {
>isNumber : (x: any) => x is number
>x : any
return typeof x === "number";
>typeof x === "number" : boolean
>typeof x : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>x : any
>"number" : "number"
}
const arrayOfStringsNumbersAndBooleans = ["string", false, 0, "strung", 1, true];
>arrayOfStringsNumbersAndBooleans : (string | number | boolean)[]
>["string", false, 0, "strung", 1, true] : (string | number | boolean)[]
>"string" : "string"
>false : false
>0 : 0
>"strung" : "strung"
>1 : 1
>true : true
const foundNumber: number | undefined = arrayOfStringsNumbersAndBooleans.find(isNumber);
>foundNumber : number
>arrayOfStringsNumbersAndBooleans.find(isNumber) : number
>arrayOfStringsNumbersAndBooleans.find : { <S extends string | number | boolean>(predicate: (this: void, value: string | number | boolean, index: number, obj: (string | number | boolean)[]) => value is S, thisArg?: any): S; (predicate: (value: string | number | boolean, index: number, obj: (string | number | boolean)[]) => boolean, thisArg?: any): string | number | boolean; }
>arrayOfStringsNumbersAndBooleans : (string | number | boolean)[]
>find : { <S extends string | number | boolean>(predicate: (this: void, value: string | number | boolean, index: number, obj: (string | number | boolean)[]) => value is S, thisArg?: any): S; (predicate: (value: string | number | boolean, index: number, obj: (string | number | boolean)[]) => boolean, thisArg?: any): string | number | boolean; }
>isNumber : (x: any) => x is number
const readonlyArrayOfStringsNumbersAndBooleans = arrayOfStringsNumbersAndBooleans as ReadonlyArray<string | number | boolean>;
>readonlyArrayOfStringsNumbersAndBooleans : ReadonlyArray<string | number | boolean>
>arrayOfStringsNumbersAndBooleans as ReadonlyArray<string | number | boolean> : ReadonlyArray<string | number | boolean>
>arrayOfStringsNumbersAndBooleans : (string | number | boolean)[]
const readonlyFoundNumber: number | undefined = readonlyArrayOfStringsNumbersAndBooleans.find(isNumber);
>readonlyFoundNumber : number
>readonlyArrayOfStringsNumbersAndBooleans.find(isNumber) : number
>readonlyArrayOfStringsNumbersAndBooleans.find : { <S extends string | number | boolean>(predicate: (this: void, value: string | number | boolean, index: number, obj: ReadonlyArray<string | number | boolean>) => value is S, thisArg?: any): S; (predicate: (value: string | number | boolean, index: number, obj: ReadonlyArray<string | number | boolean>) => boolean, thisArg?: any): string | number | boolean; }
>readonlyArrayOfStringsNumbersAndBooleans : ReadonlyArray<string | number | boolean>
>find : { <S extends string | number | boolean>(predicate: (this: void, value: string | number | boolean, index: number, obj: ReadonlyArray<string | number | boolean>) => value is S, thisArg?: any): S; (predicate: (value: string | number | boolean, index: number, obj: ReadonlyArray<string | number | boolean>) => boolean, thisArg?: any): string | number | boolean; }
>isNumber : (x: any) => x is number
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