Nano-Lisp The Tutorial Handbook

There are several type notions and in this documentation only the notion of implemen-tation type (itype in short) is considered. There are only nine itypes in Nano-Lisp: • itype: the itype of itype descriptors; • error: the itype of error messages; • boolean: the itype of boolean-objects; • symbol: the itype of Nano-Lisp symbols; • list: the itype of Nano-Lisp lists; • lambda: the itype of user-defined functions; • macro: the itype of user-defined macro definitions; • special: the itype of predefined Nano-Lisp functional objects; • system: the itype of “system ” functional objects. Each Nano-Lisp object has one and only one itype, so that the set of itypes defines a partition of the (countable) set of Nano-Lisp objects in nine subsets. The user can only enter objects made of symbols and lists; such an object is an input-object. A symbol is a character-string satisfying the traditional rules of programming lan