Regex Tester & Validator

This regex matches Objective-C code where a property or variable is declared with a 'strong' reference type followed by a pointer to a 'ViewController' class. It uses a negative lookahead to ensure that the word 'ViewController' does not appear between the 'strong' keyword and the final 'ViewController *' type declaration. Developers can use this pattern during code reviews to hunt down potential retain cycles in iOS applications, which often occur when holding strong references to view controllers.