> BTW, a long ago in order or incorporate CL into Symbolics Zeta Lisp they used cl: prefix for some functions. Nothing is new under the Moon.) 'cl:' is no pref

> BTW, a long ago in order or incorporate CL into Symbolics Zeta Lisp they used cl: prefix for some functions. Nothing is new under the Moon.) 'cl:' is no prefix in Zetalisp. Zetalisp uses packages (namespaces for symbols) just like Common Lisp, and 'cl' is the name of a package and ':' is the separator from package name and symbol name. A single colon shows that the symbol is exported - some part of an external interface. Thus cl:let is the 'let' exported from the 'cl' package. Emacs Lisp has no packages, no namespaces, no exports, imports, ... So 'cl-' is a part of the symbol name. It's just a prefix.