;;; Library
+
+(eval-when-compile
+ (%compile-defmacro 'defmacro
+ (lambda (name args &rest body)
+ `(eval-when-compile
+ (%compile-defmacro ',name (lambda ,args ,@body))))))
+
+(defmacro defvar (name value)
+ `(progn
+ (eval-when-compile
+ (%compile-defvar ',name))
+ (setq ,name ,value)))
+
+(defvar t 't)
+(defvar nil 'nil)
+
+(defmacro defun (name args &rest body)
+ `(progn
+ (eval-when-compile
+ (%compile-defun ',name))
+ (fsetq ,name (lambda ,args ,@body))))
+
+(defmacro when (condition &rest body)
+ `(if ,condition (progn ,@body)))
+
+(defmacro unless (condition &rest body)
+ `(if ,condition nil (progn ,@body)))
+
+(defun = (x y) (= x y))
+(defun + (x y) (+ x y))
+(defun - (x y) (- x y))
+(defun * (x y) (* x y))
+(defun / (x y) (/ x y))
+(defun 1+ (x) (+ x 1))
+(defun 1- (x) (- x 1))
+(defun zerop (x) (= x 0))
+(defun not (x) (if x nil t))
+
+(defun truncate (x y) (floor (/ x y)))
+
+(defun cons (x y ) (cons x y))
+(defun car (x) (car x))
+(defun caar (x) (car (car x)))
+(defun cadr (x) (car (cdr x)))
+(defun cdr (x) (cdr x))
+(defun cdar (x) (cdr (car x)))
+(defun cddr (x) (cdr (cdr x)))
+
+(defun append (list1 list2)
+ (if (null list1)
+ list2
+ (cons (car list1)
+ (append (cdr list1) list2))))
+
+(defun reverse-aux (list acc)
+ (if (null list)
+ acc
+ (reverse-aux (cdr list) (cons (car list) acc))))
+
+(defun reverse (list)
+ (reverse-aux list '()))
+
+(defmacro incf (x)
+ `(setq ,x (1+ ,x)))
+
+(defmacro decf (x)
+ `(setq ,x (1- ,x)))
+
+(defun length (list)
+ (let ((l 0))
+ (while (not (null list))
+ (incf l)
+ (setq list (cdr list)))
+ l))
+
+(defun mapcar (func list)
+ (if (null list)
+ '()
+ (cons (funcall func (car list))
+ (mapcar func (cdr list)))))
+
+(defmacro push (x place)
+ `(setq ,place (cons ,x ,place)))
+
+(defvar *package* (new))
+
+(defun intern (name)
+ (let ((s (get *package* name)))
+ (if s
+ s
+ (set *package* name (make-symbol name)))))
+
+(defun find-symbol (name)
+ (get *package* name))
+
+
+(defmacro cond (&rest clausules)
+ (if (null clausules)
+ nil
+ (if (eq (caar clausules) t)
+ `(progn ,@(cdar clausules))
+ `(if ,(caar clausules)
+ (progn ,@(cdar clausules))
+ (cond ,@(cdr clausules))))))
+
+(defun !reduce (func list initial)
+ (if (null list)
+ initial
+ (!reduce func
+ (cdr list)
+ (funcall func initial (car list)))))
+
+
+(defun code-char (x) x)
+(defun char-code (x) x)
+(defvar *newline* (string (code-char 10)))
+
+(defun concat (&rest strs)
+ (!reduce (lambda (s1 s2) (concat-two s1 s2))
+ strs
+ ""))
+
+;;; Concatenate a list of strings, with a separator
+(defun join (list separator)
+ (cond
+ ((null list)
+ "")
+ ((null (cdr list))
+ (car list))
+ (t
+ (concat (car list)
+ separator
+ (join (cdr list) separator)))))
+
+(defun join-trailing (list separator)
+ (if (null list)
+ ""
+ (concat (car list) separator (join-trailing (cdr list) separator))))
+
+(defun integer-to-string (x)
+ (if (zerop x)
+ "0"
+ (let ((digits nil))
+ (while (not (zerop x 0))
+ (push (mod x 10) digits)
+ (setq x (truncate x 10)))
+ (join (mapcar (lambda (d) (string (char "0123456789" d)))
+ digits)
+ ""))))
+
+(defmacro and (&rest forms)
+ (cond
+ ((null forms)
+ t)
+ ((null (cdr forms))
+ (car forms))
+ (t
+ `(if ,(car forms)
+ (and ,@(cdr forms))
+ nil))))
+
+
+(defmacro or (&rest forms)
+ (cond
+ ((null forms)
+ nil)
+ ((null (cdr forms))
+ (car forms))
+ (t
+ `(if ,(car forms)
+ t
+ (or ,@(cdr forms))))))
+
+
+(defmacro prog1 (form &rest body)
+ (let ((value (make-symbol "VALUE")))
+ `(let ((,value ,form))
+ ,@body
+ ,value)))
+
+
+(defun char= (x y) (= x y))
+
+
+;;;; Reader
+
+;;; It is a basic Lisp reader. It does not use advanced stuff
+;;; intentionally, because we want to use it to bootstrap a simple
+;;; Lisp. The main entry point is the function `ls-read', which
+;;; accepts a strings as argument and return the Lisp expression.
+(defun make-string-stream (string)
+ (cons string 0))
+
+(defun %peek-char (stream)
+ (and (< (cdr stream) (length (car stream)))
+ (char (car stream) (cdr stream))))
+
+(defun %read-char (stream)
+ (and (< (cdr stream) (length (car stream)))
+ (prog1 (char (car stream) (cdr stream))
+ (setcdr stream (1+ (cdr stream))))))
+
+(defun whitespacep (ch)
+ (or (char= ch #\space) (char= ch #\newline) (char= ch #\tab)))
+
+(defun skip-whitespaces (stream)
+ (let (ch)
+ (setq ch (%peek-char stream))
+ (while (and ch (whitespacep ch))
+ (%read-char stream)
+ (setq ch (%peek-char stream)))))
+
+(defun terminalp (ch)
+ (or (null ch) (whitespacep ch) (char= #\) ch) (char= #\( ch)))
+
+
+(defun read-until (stream func)
+ (let ((string "")
+ (ch))
+ (setq ch (%peek-char stream))
+ (while (not (funcall func ch))
+ (setq string (concat string (string ch)))
+ (%read-char stream)
+ (setq ch (%peek-char stream)))
+ string))
+
+(defun skip-whitespaces-and-comments (stream)
+ (let (ch)
+ (skip-whitespaces stream)
+ (setq ch (%peek-char stream))
+ (while (and ch (char= ch #\;))
+ (read-until stream (lambda (x) (char= x #\newline)))
+ (skip-whitespaces stream)
+ (setq ch (%peek-char stream)))))
+
+(defun %read-list (stream)
+ (skip-whitespaces-and-comments stream)
+ (let ((ch (%peek-char stream)))
+ (cond
+ ((char= ch #\))
+ (%read-char stream)
+ nil)
+ ((char= ch #\.)
+ (%read-char stream)
+ (skip-whitespaces-and-comments stream)
+ (prog1 (ls-read stream)
+ (unless (char= (%read-char stream) #\))
+ (error "')' was expected."))))
+ (t
+ (cons (ls-read stream) (%read-list stream))))))
projects / jscl.git / blobdiff