CLISP is an implementation of Common Lisp. The language is called Common Lisp. Common Lisp has an object system with classes since the early 90s. In fact it wa

CLISP is an implementation of Common Lisp. The language is called Common Lisp. Common Lisp has an object system with classes since the early 90s. In fact it was the first standardized object-oriented language. Common Lisp also has optional type declarations. Not very sophisticated, but they are there. Check out the SBCL implementation, which has a compiler which does some static type checking/inferencing. http://www.sbcl.org http://www.sbcl.org But one usually can use types/classes at runtime, too.