MutableValue

Added MutableValue property wrapper that creates a property that can be mutated in a SwiftUI view without kicking off a state change.

Sources/SwiftUIKit/Properties/MutableValue.swift

@@ -0,0 +1,59 @@
+//
+//  Mutable.swift
+//  Escape from Mystic Manor
+//
+//  Created by Kevin Mullins on 11/16/21.
+//
+
+import Foundation
+import SwiftUI
+
+/// Provides storage for my wrapped value
+class ValueStorage<T> {
+
+    /// The value being stored
+    var storedValue:T? = nil
+
+}
+
+/// Creates a property that can be mutated in a SwiftUI view without kicking off a state change.
+@propertyWrapper struct MutableValue<T> {
+    /// Provides storage for the mutating value
+    private let storage:ValueStorage = ValueStorage<T>()
+    private let name:String
+
+    /// The value being wrapped.
+    var wrappedValue:T {
+        get {
+            if name != "" {
+                print("Fetching \(name): \(storage.storedValue!)")
+            }
+            return storage.storedValue!
+        }
+        nonmutating set {
+            storage.storedValue = newValue
+            if name != "" {
+                print("Setting \(name): \(storage.storedValue!)")
+            }
+        }
+    }
+
+    // The value can be bound to SwiftUI
+    var projectedValue: Binding<T> {
+        Binding(
+            get: { wrappedValue },
+            set: { wrappedValue = $0 }
+        )
+    }
+
+    // Initializers
+    /// Initializes the mutating value.
+    /// - Parameter wrappedValue: The initial value for the property.
+    init(wrappedValue:T, name:String = "") {
+        self.storage.storedValue = wrappedValue
+        self.name = name
+        if name != "" {
+            print("Initializing \(name): \(wrappedValue)")
+        }
+    }
+}