Lisp interpreter implemented with C++

You can find the source code here

Architecture

• Tokenizer
• Text Parser
• BuiltIn
• Environment
• AST
• Macro Compiler
• Evaluator

Architecture

Features

true	*	==	>	or	list	rm_head	cons	foldl
false	/	<=	def	if	push_back	rm_tail	max	map
+	%	>=	set	while	head	nth_element	min
-	!	<	and	func	tail	size	filter

Sample of Abstract Syntax Tree

Fibonacci sequence recuesive version

(function fib (n) 
  (if 
    (< n 2) 
    n 
    (+ 
      (fib (- n 1)) 
      (fib (- n 2))
    )
  )
)

Sample of Abstract Syntax Tree

Sample Results

Fibonacci sequence iterative version

(def a (list 0 1 1))
(function fib(n) 
  (while 
    (< (size a) n)  
      (push_back a  
      (+
        (nth_element(- (size a) 1) a)
        (nth_element(- (size a) 2) a)
      )
    )
  )
)

result of iterative fibonacci sequence

Function and Higher Order Function

Example of the filter function.

(def a (list 1 2 3 4))
(function even (x)
  (if
    (== (% x 2) 0)
    true
    false
   )
)
(filter even a)

result of filter

Example of foldl function.

(def a (list 1 2 3 4))
(function sum(x y) (+ x y))
(foldl sum 10 a)

result of fold

You can also implement your own logic for map, foldl and filter function.

Function Overloading

Example of sum function overloading.

(function add (a b) (+ a b))
(function add (a b c) (+ a b c))

result of function overloading