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=== tests/cases/compiler/voidUndefinedReduction.ts ===
// Repro from #42786
function isDefined<T>(value: T | undefined | null | void): value is T {
>isDefined : <T>(value: T | undefined | null | void) => value is T
>value : void | T | null | undefined
>null : null
return value !== undefined && value !== null;
>value !== undefined && value !== null : boolean
>value !== undefined : boolean
>value : void | T | null | undefined
>undefined : undefined
>value !== null : boolean
>value : (T & {}) | null
>null : null
}
declare const foo: string | undefined;
>foo : string | undefined
if (isDefined(foo)) {
>isDefined(foo) : boolean
>isDefined : <T>(value: void | T | null | undefined) => value is T
>foo : string | undefined
console.log(foo.toUpperCase());
>console.log(foo.toUpperCase()) : void
>console.log : (...data: any[]) => void
>console : Console
>log : (...data: any[]) => void
>foo.toUpperCase() : string
>foo.toUpperCase : () => string
>foo : string
>toUpperCase : () => string
}
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