TypeScript/tests/baselines/reference/narrowingUnionByUnionCandidate1.types at 29ae00ac0f6b255cf3bfcad3967fed0a4e245e27 · Andarist/TypeScript · GitHub

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//// [tests/cases/compiler/narrowingUnionByUnionCandidate1.ts] ////

=== narrowingUnionByUnionCandidate1.ts ===
// https://github.com/microsoft/TypeScript/issues/61581

type Result<A, E> =
>Result : Result<A, E>
>       : ^^^^^^^^^^^^

  | {
      readonly _tag: "Ok";
>_tag : "Ok"
>     : ^^^^

      readonly value: A;
>value : A
>      : ^
    }
  | {
      readonly _tag: "Fail";
>_tag : "Fail"
>     : ^^^^^^

      readonly error: E;
>error : E
>      : ^

    };

declare const isResult: (u: unknown) => u is Result<any, any>;
>isResult : (u: unknown) => u is Result<any, any>
>         : ^ ^^       ^^^^^
>u : unknown
>  : ^^^^^^^

// return type: Result<A, E> | "ok"
export const fn = <A, E>(inp: Result<A, E> | string) =>
>fn : <A, E>(inp: Result<A, E> | string) => Result<A, E> | "ok"
>   : ^ ^^ ^^   ^^                     ^^^^^^^^^^^^^^^^^^^^^^^^
><A, E>(inp: Result<A, E> | string) =>  isResult(inp) ? inp : "ok" : <A, E>(inp: Result<A, E> | string) => Result<A, E> | "ok"
>                                                                  : ^ ^^ ^^   ^^                     ^^^^^^^^^^^^^^^^^^^^^^^^
>inp : string | Result<A, E>
>    : ^^^^^^^^^^^^^^^^^^^^^

  isResult(inp) ? inp : "ok";
>isResult(inp) ? inp : "ok" : Result<A, E> | "ok"
>                           : ^^^^^^^^^^^^^^^^^^^
>isResult(inp) : boolean
>              : ^^^^^^^
>isResult : (u: unknown) => u is Result<any, any>
>         : ^ ^^       ^^^^^
>inp : string | Result<A, E>
>    : ^^^^^^^^^^^^^^^^^^^^^
>inp : Result<A, E>
>    : ^^^^^^^^^^^^
>"ok" : "ok"
>     : ^^^^