;;; Utils
+#+common-lisp
(defmacro while (condition &body body)
`(do ()
((not ,condition))
strs
:initial-value ""))
-
-(let ((counter 0))
- (defun make-var-binding (symbol)
- (cons symbol (format nil "v~d" (incf counter)))))
-
-(let ((counter 0))
- (defun make-func-binding (symbol)
- (cons symbol (format nil "f~d" (incf counter)))))
-
-
;;; Concatenate a list of strings, with a separator
(defun join (list separator)
(cond
separator
(join (cdr list) separator)))))
-;;; Compiler
+(defun integer-to-string (x)
+ (if (zerop x)
+ "0"
+ (let ((digits nil))
+ (while (not (= x 0))
+ (push (mod x 10) digits)
+ (setq x (truncate x 10)))
+ (join (mapcar (lambda (d) (string (char "0123456789" d)))
+ digits)
+ ""))))
+
+;;;; 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)
+ (if (streamp stream)
+ (peek-char nil stream nil)
+ (and (< (cdr stream) (length (car stream)))
+ (char (car stream) (cdr stream)))))
+
+(defun %read-char (stream)
+ (if (streamp stream)
+ (read-char stream nil)
+ (and (< (cdr stream) (length (car stream)))
+ (prog1 (char (car stream) (cdr stream))
+ (incf (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= #\( ch)))
+
+(defun read-until (stream func)
+ (let ((string "")
+ (ch))
+ (setq ch (%peek-char stream))
+ (while (not (funcall func ch))
+ (setq string (concat string (string ch)))
+ (%read-char stream)
+ (setq ch (%peek-char stream)))
+ string))
+
+(defun skip-whitespaces-and-comments (stream)
+ (let (ch)
+ (skip-whitespaces stream)
+ (setq ch (%peek-char stream))
+ (while (and ch (eql ch #\;))
+ (read-until stream (lambda (x) (eql x #\newline)))
+ (skip-whitespaces stream)
+ (setq ch (%peek-char stream)))))
+
+(defun %read-list (stream)
+ (skip-whitespaces-and-comments stream)
+ (let ((ch (%peek-char stream)))
+ (cond
+ ((char= ch #\))
+ (%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))))))
+
+(defvar *eof* (make-symbol "EOF"))
+(defun ls-read (stream)
+ (skip-whitespaces-and-comments stream)
+ (let ((ch (%peek-char stream)))
+ (cond
+ ((null ch)
+ *eof*)
+ ((char= ch #\()
+ (%read-char stream)
+ (%read-list stream))
+ ((char= ch #\')
+ (%read-char stream)
+ (list 'quote (ls-read stream)))
+ ((char= ch #\`)
+ (%read-char stream)
+ (list 'backquote (ls-read stream)))
+ ((char= ch #\")
+ (%read-char stream)
+ (prog1 (read-until stream (lambda (ch) (char= ch #\")))
+ (%read-char stream)))
+ ((char= ch #\,)
+ (%read-char stream)
+ (if (eql (%peek-char stream) #\@)
+ (progn (%read-char stream) (list 'unquote-splicing (ls-read stream)))
+ (list 'unquote (ls-read stream))))
+ ((char= ch #\#)
+ (%read-char stream)
+ (ecase (%read-char stream)
+ (#\'
+ (list 'function (ls-read stream)))
+ (#\+
+ (let ((feature (read-until stream #'terminalp)))
+ (cond
+ ((string= feature "common-lisp")
+ (ls-read stream);ignore
+ (ls-read stream))
+ ((string= feature "lispstrack")
+ (ls-read stream))
+ (t
+ (error "Unknown reader form.")))))))
+ (t
+ (let ((string (read-until stream #'terminalp)))
+ (if (every #'digit-char-p string)
+ (parse-integer string)
+ (intern (string-upcase string))))))))
+
+(defun ls-read-from-string (string)
+ (ls-read (make-string-stream string)))
+
+
+;;;; Compiler
+
+(let ((counter 0))
+ (defun make-var-binding (symbol)
+ (cons symbol (concat "v" (integer-to-string (incf counter))))))
+
+(let ((counter 0))
+ (defun make-func-binding (symbol)
+ (cons symbol (concat "f" (integer-to-string (incf counter))))))
(defvar *compilations* nil)
(defun ls-lookup (symbol env)
(let ((binding (assoc symbol env)))
- (and binding (format nil "~a" (cdr binding)))))
+ (and binding (cdr binding))))
(defun lookup-variable (symbol env)
(or (ls-lookup symbol env)
`(push (list ',name (lambda (env fenv ,@args) ,@body))
*compilations*))
+(defvar *toplevel-compilations*)
+
(define-compilation if (condition true false)
- (format nil "((~a)? (~a) : (~a))"
+ (concat "("
(ls-compile condition env fenv)
+ " ? "
(ls-compile true env fenv)
- (ls-compile false env fenv)))
+ " : "
+ (ls-compile false env fenv)
+ ")"))
;;; Return the required args of a lambda list
(defun lambda-list-required-argument (lambda-list)
})"))))
(define-compilation fsetq (var val)
- (format nil "~a = ~a" (lookup-function var fenv) (ls-compile val env fenv)))
+ (concat (lookup-function var fenv)
+ " = "
+ (ls-compile val env fenv)))
(define-compilation setq (var val)
- (format nil "~a = ~a" (lookup-variable var env) (ls-compile val env fenv)))
+ (concat (lookup-variable var env)
+ " = "
+ (ls-compile val env fenv)))
;;; Literals
-(defvar *literals* '())
-
(defun literal->js (sexp)
(cond
((null sexp) "undefined")
- ((integerp sexp) (format nil "~a" sexp))
- ((stringp sexp) (format nil "\"~a\"" sexp))
- ((symbolp sexp) (format nil "{name: \"~a\"}" (symbol-name sexp)))
+ ((integerp sexp) (integer-to-string sexp))
+ ((stringp sexp) (concat "\"" sexp "\""))
+ ((symbolp sexp) (concat "{name: \"" (symbol-name sexp) "\"}"))
((consp sexp) (concat "{car: "
(literal->js (car sexp))
", cdr: "
(let ((counter 0))
(defun literal (form)
- (let ((var (format nil "l~d" (incf counter))))
- (push (cons var (literal->js form)) *literals*)
+ (let ((var (concat "l" (integer-to-string (incf counter)))))
+ (push (concat "var " var " = " (literal->js form)) *toplevel-compilations*)
var)))
(define-compilation quote (sexp)
(literal sexp))
(define-compilation debug (form)
- (format nil "console.log(~a)" (ls-compile form env fenv)))
+ (concat "console.log(" (ls-compile form env fenv) ")"))
(define-compilation while (pred &rest body)
- (format nil "(function(){while(~a){~a}})() "
- (ls-compile pred env fenv)
- (ls-compile-block body env fenv)))
+ (concat "(function(){ while("
+ (ls-compile pred env fenv)
+ "){"
+ (ls-compile-block body env fenv)
+ "}})()"))
+
+(define-compilation function (x)
+ (cond
+ ((and (listp x) (eq (car x) 'lambda))
+ (ls-compile x env fenv))
+ ((symbolp x)
+ (lookup-function x fenv))))
(defmacro eval-when-compile (&body body)
`(eval-when (:compile-toplevel :execute)
(defvar *eval-when-compilations*)
(define-compilation eval-when-compile (&rest body)
- (setq *eval-when-compilations* "")
(eval (cons 'progn body))
- (if (string= *eval-when-compilations* "")
- nil
- *eval-when-compilations*))
-
+ nil)
(defmacro define-transformation (name args form)
`(define-compilation ,name ,args
`((lambda ,(mapcar 'car bindings) ,@body)
,@(mapcar 'cadr bindings)))
-;;; aritmetic primitives
+;;; A little backquote implementation without optimizations of any
+;;; kind for lispstrack.
+(defun backquote-expand-1 (form)
+ (cond
+ ((symbolp form)
+ (list 'quote form))
+ ((atom form)
+ form)
+ ((eq (car form) 'unquote)
+ (car form))
+ ((eq (car form) 'backquote)
+ (backquote-expand-1 (backquote-expand-1 (cadr form))))
+ (t
+ (cons 'append
+ (mapcar (lambda (s)
+ (cond
+ ((and (listp s) (eq (car s) 'unquote))
+ (list 'list (cadr s)))
+ ((and (listp s) (eq (car s) 'unquote-splicing))
+ (cadr s))
+ (t
+ (list 'list (backquote-expand-1 s)))))
+ form)))))
+
+(defun backquote-expand (form)
+ (if (and (listp form) (eq (car form) 'backquote))
+ (backquote-expand-1 (cadr form))
+ form))
+
+(define-transformation backquote (form)
+ (backquote-expand-1 form))
+
+;;; Primitives
+
(define-compilation + (x y)
(concat "((" (ls-compile x env fenv) ") + (" (ls-compile y env fenv) "))"))
(define-compilation eq (x y)
(concat "(" (ls-compile x env fenv) " === " (ls-compile y env fenv) ")"))
-
-
-(defmacro with-eval-when-compilation (&body body)
- `(setq *eval-when-compilations*
- (concat *eval-when-compilations* (progn ,@body))))
+(define-compilation code-char (x)
+ (concat "String.fromCharCode( " (ls-compile x env fenv) ")"))
(defun %compile-defvar (name)
(push (make-var-binding name) *env*)
- (with-eval-when-compilation
- (format nil "var ~a" (lookup-variable name *env*))))
+ (push (concat "var " (lookup-variable name *env*)) *toplevel-compilations*))
(defun %compile-defun (name)
(push (make-func-binding name) *fenv*)
- (with-eval-when-compilation
- (format nil "var ~a" (lookup-variable name *fenv*))))
+ (push (concat "var " (lookup-variable name *fenv*)) *toplevel-compilations*))
(defun %compile-defmacro (name lambda)
(push (cons name (cons 'macro lambda)) *fenv*))
(defun compile-funcall (function args env fenv)
(cond
((symbolp function)
- (format nil "~a(~{~a~^, ~})"
- (lookup-function function fenv)
- (mapcar (lambda (x) (ls-compile x env fenv)) args)))
+ (concat (lookup-function function fenv)
+ "("
+ (join (mapcar (lambda (x) (ls-compile x env fenv)) args)
+ ", ")
+ ")"))
((and (listp function) (eq (car function) 'lambda))
- (format nil "(~a)(~{~a~^, ~})"
- (ls-compile function env fenv)
- (mapcar (lambda (x) (ls-compile x env fenv)) args)))
+ (concat "(" (ls-compile function env fenv) ")("
+ (join (mapcar (lambda (x) (ls-compile x env fenv)) args)
+ ", ")
+ ")"))
(t
(error "Invalid function designator ~a." function))))
(defun ls-compile (sexp &optional env fenv)
(cond
((symbolp sexp) (lookup-variable sexp env))
- ((integerp sexp) (format nil "~a" sexp))
- ((stringp sexp) (format nil "\"~a\"" sexp))
+ ((integerp sexp) (integer-to-string sexp))
+ ((stringp sexp) (concat "\"" sexp "\""))
((listp sexp)
(let ((sexp (ls-macroexpand-1 sexp env fenv)))
(let ((compiler-func (second (assoc (car sexp) *compilations*))))
(compile-funcall (car sexp) (cdr sexp) env fenv)))))))
(defun ls-compile-toplevel (sexp)
- (setq *literals* nil)
+ (setq *toplevel-compilations* nil)
(let ((code (ls-compile sexp)))
(prog1
- (concat (join (mapcar (lambda (lit)
- (concat "var " (car lit) " = " (cdr lit) ";
+ (concat (join (mapcar (lambda (x)(concat x ";
"))
- *literals*)
+ *toplevel-compilations*)
"")
code)
- (setq *literals* nil))))
-
+ (setq *toplevel-compilations* nil))))
+#+common-lisp
(defun ls-compile-file (filename output)
(with-open-file (in filename)
(with-open-file (out output :direction :output :if-exists :supersede)
(loop
- for x = (read in nil) while x
+ for x = (ls-read in)
+ until (eq x *eof*)
for compilation = (ls-compile-toplevel x)
when compilation do (write-line (concat compilation "; ") out)))))
-
;;; Testing
-
(defun compile-test ()
(ls-compile-file "test.lisp" "test.js"))