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|
=== tests/cases/compiler/partialTypeNarrowedToByTypeGuard.ts ===
type Obj = {} | undefined;
>Obj : {} | undefined
type User = {
>User : { email: string; name: string; }
email: string;
>email : string
name: string;
>name : string
};
type PartialUser = Partial<User>;
>PartialUser : Partial<User>
// type PartialUser = {
// email?: string;
// name?: string;
// };
function isUser(obj: Obj): obj is PartialUser {
>isUser : (obj: Obj) => obj is Partial<User>
>obj : Obj
return true;
>true : true
}
function getUserName(obj: Obj) {
>getUserName : (obj: Obj) => string | undefined
>obj : Obj
if (isUser(obj)) {
>isUser(obj) : boolean
>isUser : (obj: Obj) => obj is Partial<User>
>obj : Obj
return obj.name;
>obj.name : string | undefined
>obj : Partial<User>
>name : string | undefined
}
return '';
>'' : ""
}
|
