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Examples/React Meets SwiftUI/Context.md

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+## Context
+
+You can replicate the context functionality found in React by using a combination of `BindableObject`, `Combine` and defining an `environmentObject` for a View. You create a class that adheres to the `BindableObject` and provide that as an argument to `environmentObject` when initiating your parent view. Any child of that parent view can then access the class using `@EnvironmentObject`.
+
+### React
+
+```jsx
+import React, { useContext } from "react";
+
+const Session = React.createContext({ name: "" });
+
+export function ContextProvider() {
+  return (
+    <Session.Provider value={{ name: "Bento" }}>
+      <Parent />
+    </Session.Provider>
+  );
+}
+
+export function Parent() {
+  return <Child />;
+}
+
+export function Child() {
+  const session = useContext(Session);
+
+  return <span>Hello {session.name}</span>;
+}
+```
+
+### SwiftUI
+
+```swift
+import SwiftUI
+import Combine
+
+final class Session: BindableObject {
+    let didChange = PassthroughSubject<Session, Never>()
+
+    var name: String {
+        didSet { didChange.send(self) }
+    }
+
+    init(name: String) {
+        self.name = name
+    }
+}
+
+
+struct ContextProvider : View {
+    var body: some View {
+        Parent().environmentObject(Session(name: "Bento"))
+    }
+}
+
+struct Parent : View {
+    var body: some View {
+        Child()
+    }
+}
+
+struct Child : View {
+
+    @EnvironmentObject var session: Session
+
+    var body: some View {
+        Text("Hello \(session.name)")
+    }
+}
+```