Ruby has at least 1. and 3. 1. "usable global variables" exist in two forms; the rarely used $ sigil, as in $foo (automatically global), and the more commonly

Ruby has at least 1. and 3. 1. "usable global variables" exist in two forms; the rarely used $ sigil, as in $foo (automatically global), and the more commonly used hack of defining attributes and accessors on a class (for which there's standard macrology, cattr_accessor, in Rails). 3. Everything he mentions as properties of Lisp closures is commonly done with Ruby blocks (modifying variables in enclosing scopes; use of "return" in a block to return from the enclosing method). That leaves the condition system. I'm not aware of another commonly used environment that lets you say, for instance, "if you were about to throw a FileNotFound exception, try doing this instead first". But unlike the other two, I'm not sure that's a feature of Lisp dialects in general, as Common Lisp in particular...