isResult

@ts-rust/std

---

@ts-rust/std / Result / isResult

Function: isResult()

function isResult(x): x is Result<unknown, unknown>;

Defined in: packages/std/src/result/result.ts:473

Checks if a value is a Result, narrowing its type to Result<unknown, unknown>.

This type guard verifies whether the input conforms to the Result interface, indicating it is either an Ok or Err.

Parameters

Parameter	Type	Description
x	unknown	The value to check.

Returns

x is Result<unknown, unknown>

true if the value is a Result, narrowing to Result<unknown, unknown>.

Example

const x: unknown = ok<number, string>(42);
const y: unknown = err<number, string>("failure");
const z: unknown = "not a result";

expect(isResult(x)).toBe(true);
expect(isResult(y)).toBe(true);
expect(isResult(z)).toBe(false);

if (isResult(x)) {
  expect(x.isOk()).toBe(true); // Type narrowed to Result<unknown, unknown>
}