Macro WITH-UNIQUE-NAMES Evaluate BODY with BINDINGS bound to fresh unique symbols.
Macro REBINDING Bind each var in BINDINGS to a gensym, bind the gensym to var's value via a let, return BODY's value wrapped in this let.
Macro WITH-ACCESSORS* Just like WITH-ACCESSORS, but if the slot-entry is a symbol assume the variable and accessor name are the same.
Macro DEFINE-CONSTANT DEFCONSTANT with extra EXPORT-P argument.