Add forceCastedValue()

Author: devxoul

README.md

@@ -12,6 +12,7 @@ A weak-to-strong map table. It is inspired by [`NSMapTable`](https://developer.a
 ```swift
 public func value(forKey key: Key) -> Value?
 public func value(forKey key: Key, default: @autoclosure () -> Value) -> Value
+public func forceCastedValue<T>(forKey key: Key, default: @autoclosure () -> T) -> T
 public func setValue(_ value: Value?, forKey key: Key)
 ```
 

Sources/WeakMapTable/WeakMapTable.swift

@@ -46,6 +46,10 @@ final public class WeakMapTable<Key, Value> where Key: AnyObject {
     return defaultValue
   }
 
+  public func forceCastedValue<T>(forKey key: Key, default: @autoclosure () -> T) -> T {
+    return self.value(forKey: key, default: `default`() as! Value) as! T
+  }
+
   public func setValue(_ value: Value?, forKey key: Key) {
     let weakKey = Weak(key)