Update README.md

README.md

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-# swiftui-layout-guides
- Expose layout margins and readable content width to SwiftUI's Views
+# SwiftUI Layout Guides
+This micro-library exposes UIKit's layout margins and readable content guides to SwiftUI.
+
+## Usage
+### Make a view fit the readable content width
+Simply call the `fitToReadableContentWidth()` modifier:
+```swift
+List {
+ ForEach(…) {
+   Cell()
+     .fitToReadableContentWidth()
+ }
+}
+```
+### Expose the layout margins in a block
+Wrap your view in the `WithLayoutMargins` view. The initializer supports two variants: one closure without argument and one closure with a `EdgeInsets` argument. In this last case, the insets correspond to the layout margins for the content:
+```swift
+WithLayoutMargins { layoutMarginsInsets in
+ Text("ABC")
+   .padding(.leading, layoutMarginsInsets.leading) 
+}
+```
+### Expose layout margins and readable content guides in a view
+You need two wrap your view in `WithLayoutMargins` (you can use the argument-less closure). This will populate the content's `Environment` with the layout margins and readable content in the form of insets. 
+```swift
+WithLayoutMargins {
+ Content()
+}
+
+struct Content: View {
+  @Environment(\.layoutMarginsInsets) var layoutMarginsInsets
+  @Environment(\.readableContentInsets) var readableContentInsets
+  var body: some View {
+    Text("ABC")
+      .padding(.leading, layoutMarginsInsets.leading)
+      …
+  }
+}
+```
+These insets are only valid for the bounds of the root content view. Using them deeper in the hierachy may lead to insconsitent results.
+
+## Installation
+Add `.package(url: "https://github.com/tgrapperon/swiftui-layout-guides", from: "0.0.2")` to your Package dependencies, and then 
+```
+.product(name: "SwiftUILayoutGuides", package: "swiftui-layout-guides")
+```
+to your target's dependencies.
+