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# subscript(_:)

Gets the value of the given horizontal guide.

```
subscript(guide: HorizontalAlignment) -> CGFloat { get }
```

## Overview

Find the offset of a particular guide in the corresponding view by
using that guide as an index to read from the context:

```
.alignmentGuide(.leading) { context in
    context[.leading] - 10
}
```

For information about using subscripts in Swift to access member
elements of a collection, list, or, sequence, see
[Subscripts](https://docs.swift.org/swift-book/LanguageGuide/Subscripts.html)
in *The Swift Programming Language*.

---

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