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# EnumeratedSequence.Index

A type that represents a position in the collection.

```
@frozen struct Index
```

## Overview

Valid indices consist of the position of every element and a
“past the end” position that’s not valid for use as a subscript
argument.

## Topics

### Instance Properties

[`let base: Base.Index`](/documentation/Swift/EnumeratedSequence/Index/base)

The position in the underlying collection.

### Default Implementations

[Comparable Implementations](/documentation/Swift/EnumeratedSequence/Index/Comparable-Implementations)

[Equatable Implementations](/documentation/Swift/EnumeratedSequence/Index/Equatable-Implementations)

## Relationships

### Conforms To

[`Equatable`](/documentation/Swift/Equatable)

[`Comparable`](/documentation/Swift/Comparable)

---

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