Add mixin for boilerplate workaround

README.md

@@ -126,14 +126,20 @@ Known issues
 * Due to preventive measures of recursion issues in circular dependencies, registrations which are supposed to yield new instances will not autowire classes for which a circular dependency is detected. A new instance will be resolved but the instance's members will not be autowired.
 * Resolving a class registered by supertype or interface will only autowire the members inherited from its supertypes and in the case of interfaces none at all. A workaround for this issue is to autowire members in the constructor of a class:
 ```d
+import poodinis.autowire;
+
 class ComponentF {
 	@Autowire
 	public ComponentA componentA;
 	
 	public this() {
 		auto container = Container.getInstance();
-		container.autowire!ComponentF(this);
+		container.autowire!(typeof(this))(this);
 	}
+	
+	// or use:
+	// mixin AutowireConstructor;
+	// which adds the constructor above
 }
 ```
 

source/poodinis/autowire.d

@@ -37,3 +37,10 @@ public void autowire(Type)(Container container, Type instance) {
 		}
 	}
 }
+
+mixin template AutowireConstructor() {
+	public this() {
+		auto __container = Container.getInstance();
+		__container.autowire!(typeof(this))(this);
+	}
+}

test/poodinis/autowiretest.d

@@ -46,10 +46,7 @@ version(unittest) {
 		@Autowire
 		public ComponentA componentA;
 		
-		public this() {
-			auto container = Container.getInstance();
-			container.autowire!(typeof(this))(this);
-		}
+		mixin AutowireConstructor;
 	}
 	
 	// Test autowiring concrete type to existing instance