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# consuming(_:startingAt:in:)

Process the input string within the specified bounds, beginning at the given index, and return
the end position (upper bound) of the match and the produced output.

```
func consuming(_ input: String, startingAt index: String.Index, in bounds: Range<String.Index>) throws -> (upperBound: String.Index, output: Self.RegexOutput)?
```

## Parameters

`input`

The string in which the match is performed.

`index`

An index of `input` at which to begin matching.

`bounds`

The bounds in `input` in which the match is performed.

## Return Value

The upper bound where the match terminates and a matched instance, or `nil` if
there isn’t a match.

---

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