README.md

tl, Tony's Lisp

A simple lisp implementation (Build you own Lisp)

Try it

make BUILD=RELEASE run

create a short hand function for defining global functions using lambda (\)

(def {fn} 
  (\ {fargs body} 
    {def (head fargs) (\ (tail fargs) body) }))
; then
(fn {fname args...} {body})

otherwise

def {fname} (\ {arg1 arg2 ...} body)

fibonacci

;; with recursion
(fn {fib n}
  {if (|| (== n 1) (== n 2))
    {1}
    {+ (fib (- n 1)) (fib (- n 2))}})
;; with closure (closures must be defined using lambda)
(fn {fib2 n} { do
  (= {helper}
    (\ {n2 l} {
      if (== n n2) 
        {l}
        {helper (+ n2 1)
          (list (second l) (+ (first l) (second l)))}}
  ))
  (first (helper 0 {0 1}))
})

tl only wraps log from <math.h> as ln which is natural logarithm.

;; log_x (y)
(fn {log x y}
  {div (ln y) (ln x)})
(log 4.0 16.0)
2.000000

Language

• double: any forms of numbers stored using double in C
• integer: as int, and boolean type
• string: "..."
• symbol: unique identifier of a piece of resource
• comment: ;...
• s-expr: ( expression*... )
• q-expr: { expression*... }
• expression: s-expr | q-expr | double | integer | symbol | comment
• tl (lisp): expression*

Builtin

• integer math operation: + - * /
• double operator: add sub mul div mod pow exp ln
• Q-Expression (list): list head tail join eval
• Environment: def, =, dir, echo, lambda

Implementation

Parser

Lexing is being kept as a black box using library from libmpc.

The abstract symtax tree

TODO

• hash map for symbol lookup map.c
• pool allocation mpool.c
• gc
• wrap os function