LISP on browser¶

Design¶

Readability counts.

My goal is not to make complete features of Lisp. It makes source codes huge and makes difficult to read.

TODO¶

• (done) Milestone1: S-expression Parser
  • given string such like “(* 1 (+ 2 3))” and return syntax trees
  • in this point forget about reader macros such as “’(1 2 3)”
• (done) Milestone2: Some Built-in function
  • arithmetic functions: +, -, *, /
  • other functions: eval, cons, list
• (done) Milestone3: A REPL interpreter(when user input (* 1 (+ 2 3)), it prints 5)
  • Now we can (* 1 (+ 2 3))
• (done) Milestone4: Special forms: quote and if
• (done) Milestone5: Reader syntax with apostrophe: ‘(+ 2 2) = (quote (+ 2 2))
• Milestone6: equality and comparison: =, /=, <, etc.
• Milestone7: comments in the code
• Milestone8: a textbox for loading examples into interpreter
• Milestone9: lexical scope (let and variables)
• Milestone10: defining your own functions (defun)

• Now we can make factorial and counter

• Further milestones (need to break into smaller milestones)
  • Strings, I/O (print, read) using terminal
  • Macros (and quasiquote/unquote)

; factorial
(defun factorial (n) (if (= n 0) 1 (* n (factorial (- n 1)))))

; counter
gosh> (define (counter)
  (let ((count 0))
     (lambda () (set! count (+ 1 count)))))
counter
gosh> (define c (counter))
c
gosh> (c)
1
gosh> (c)
2
gosh> (c)
3

License¶

GPLv3

Thanks¶

Paweł Marczewski wrote almost codes.