# Errors

> USearch for C++

`#include <usearch/dense_index.hpp>`

## outcome

A call's first output beside its status and static message, decomposed as `auto [value, status, message]`; the value is meaningful only on success.

```cpp
template <typename value_type_ = void>
struct outcome
```

- `value` `value_type_`
- `status` `usearch_status_t`
- `message` `char const *`

## outcome< void >

The outcome of a call that outputs nothing but its status.

```cpp
template <>
struct outcome< void >
```

- `status` `usearch_status_t`
- `message` `char const *`
- `value` `void`