# Lisp_in_C

Program decription:

This is a simple lisp interpreter implemented in C.
Support basic variable display like NIL;
Support fundamental steps as read, eval, print, etc.
Support primal operations like '+' '-' '*' '/';
Support recursively function call using stack;
Support variable definition like "setq";
Support using variables in the basic function;

Due to the limited time, the following features are still in progress:
Function customized define like "defun".
Input check and syntax check.
More built-in functions initialization.

Program snapshot:

yangxk15s-MacBook-Pro:project yangxk15$ ./xkcl 
XKCL (Xiankai Common Lisp) Version 1.0 Tue Jun  7 02:19:11 2016

>()
NIL
>(+ 3 5)
8
>(- 3 4)
-1
>(* 2 3)
6
>(/ 8 4)
2
>(+ (- 5 2) (* 3 (/ 10 2)))
18
>(setq a 5)
5
>(+ a 5)
10
>(setq a 7)
7
>(+ a 5)
12
>(quit)
yangxk15s-MacBook-Pro:project yangxk15$