> For the complete documentation index, see [llms.txt](https://osl.mistium.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://osl.mistium.com/packages/utilities/result.md).

# result

> Success/error result values

Use `result` to return either a success value or an error value from APIs that should not throw immediately.

```javascript
import "osl/result"
```

## Example

```javascript
import "osl/result"

auto ok = result.ok(42)
log ok.unwrapOr(0)
```

## API reference

### `result`

| Method               | Returns   | Description             |
| -------------------- | --------- | ----------------------- |
| `result.ok(v: any)`  | `*Result` | Runs the ok operation.  |
| `result.err(e: any)` | `*Result` | Runs the err operation. |

### `Result` values

Methods available on `Result` values returned by this package or constructed by the language.

| Method                               | Returns   | Description                                                 |
| ------------------------------------ | --------- | ----------------------------------------------------------- |
| `value.isOk()`                       | `boolean` | Reports whether the result is successful.                   |
| `value.isErr()`                      | `boolean` | Reports whether the result is an error.                     |
| `value.unwrap()`                     | `any`     | Returns the contained value or fails.                       |
| `value.unwrapOr(def: any)`           | `any`     | Returns the contained value or a fallback.                  |
| `value.expect(msg: any)`             | `any`     | Returns the contained value or fails with a custom message. |
| `value.unwrapErr()`                  | `any`     | Returns the error value or fails.                           |
| `value.expectErr(msg: any)`          | `any`     | Runs the expect err operation.                              |
| `value.fromGo(val: any, err: error)` | `*Result` | Creates from go.                                            |

## Notes

* Standard-library imports accept both `import "osl/result"` and `import "result"`.
* Return values such as `array` and `object` are regular OSL values unless a returned object section says otherwise.