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--- rfc:callableconstructors [2016/02/25 13:23] – Fix formatting salathe
+++ rfc:callableconstructors [2016/02/25 14:04] – danack
@@ Line 139: / Line 139: @@
 ===== Backward Incompatible Changes =====
-None known
+There is a single BC break known. When the %%__%%construct method is called statically from within the scope of the containing class, and the call is made with call_user_function, rather than being called with $fn() syntax, then the function is erroneously called through the 'instance' scope, rather than through static scope.
+<code php>
+class A {
+    public function %%__%%construct() {
+        return "Why would you even do this.";
+    }
+    public function foo() {
+        $fn = [self::class, '%%__%%construct'];
+        // Calling directly as a callable like:
+        // $result = $fn();
+        // Correctly fails with the error message:
+        // Error: Non-static method A::%%__%%construct() cannot be called statically
+        // However calling with 'call user function', is erroneously allowed.
+        $result = call_user_func($fn);
+        var_dump($result);
+    }
+}
+$a = new A;
+$a->foo();
+// Current output is:
+// string(27) "Why would you even do this."
+// Output after RFC would be:
+// object(A)#1 (0) {
+// }
+</code>
+The code would need to be changed to call the %%__%%construct method through the instance to continue to have the code behave as before. i.e.
+<code php>
+$fn = [$this, '__construct'];
+//This calls the constructor as an instance method, without creating a new object, in exactly the same
+// way as `$foo->__contruct();` calls the method without creating an object.
+</code>
 ===== Proposed PHP Version =====

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