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# collectResults

Combine an array of Results into one Result. If every item succeeds, return its values in order. Otherwise return the original first failure in input order. Inspired by Rust's `Iterator::collect` into `Result<Vec<T>, E>`.

## Usage

### `collectResults(results)`

```typescript
import { collectResults, err, ok } from 'massaman/control'

collectResults([ok(1), ok(2), ok(3)])
// Ok([1, 2, 3])

const first = err('invalid email')
collectResults([ok(1), first, err('missing name'), ok(4)])
// The original first Err, not an aggregate error.

collectResults([])
// Ok([])
```

#### Parameters


resultsreadonly Result<T, E>[]required

The already-created Results to combine. Accepts readonly arrays and does not mutate inputs.

#### Returns

`Result<T[], E>`. Success creates a new array, preserving value references and order. Failure returns the first `Err` by reference, preserving its original error and custom fields. Distinct value and error types are inferred as unions; this helper does not preserve tuple positions or accept records.

#### Errors and partial successes

The output contains neither partial successes nor later errors. The input remains unchanged. Use `partitionResults` if every success and every error matters, such as validating imported rows.

#### Collection is not execution

```typescript
const parsed = collectResults(rows.map(parseRow))
```

`map` has already called `parseRow` for every row before collection starts. This helper cannot cancel that work or prevent exceptions thrown while creating the input. Use `attempt` at throwing boundaries. To stop running later operations after a failure, sequence individual Results with `andThen` instead.

Promises are not awaited. For independent asynchronous operations, await their Results first, for example `collectResults(await Promise.all(tasks))`; all tasks may already be running.

## See also

- [`partitionResults`](https://massaman.dev/reference/control/partitionResults.md) — retain every success and error
- [`andThen`](https://massaman.dev/reference/control/andThen.md) — sequence dependent fallible operations
- [Result & Errors](https://massaman.dev/concepts/result.md)