Yes, JavaScript also has a single namespace, like a Lisp-1.
The advantage of a Lisp-2 is that it makes macro writing easier; you can include calls to known functions in the expansion without having to deal with the possibility that those names have been shadowed.
The advantage of a Lisp-2 is that it makes macro writing easier; you can include calls to known functions in the expansion without having to deal with the possibility that those names have been shadowed.