X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fprint.lisp;h=02f3919ecb820bf18734d1063a7c8fdc8ce92c6d;hb=71497337d7fc99cf8eefe239e662f86c67519d57;hp=919ab3dbb0e4b6cf5919281b8b4ccf40b25f9cf9;hpb=89ee56f4f8d539db9462f50cbfd2e1b99ceb06d6;p=jscl.git

diff --git a/src/print.lisp b/src/print.lisp
index 919ab3d..02f3919 100644
--- a/src/print.lisp
+++ b/src/print.lisp
@@ -1,4 +1,4 @@
-;;; print.lisp --- 
+;;; print.lisp ---
 
 ;; Copyright (C) 2012, 2013 David Vazquez
 ;; Copyright (C) 2012 Raimon Grau
@@ -16,56 +16,297 @@
 ;; You should have received a copy of the GNU General Public License
 ;; along with JSCL.  If not, see <http://www.gnu.org/licenses/>.
 
+(/debug "loading print.lisp!")
+
 ;;; Printer
 
+(defun lisp-escape-string (string)
+  (let ((output "")
+        (index 0)
+        (size (length string)))
+    (while (< index size)
+      (let ((ch (char string index)))
+        (when (or (char= ch #\") (char= ch #\\))
+          (setq output (concat output "\\")))
+        (when (or (char= ch #\newline))
+          (setq output (concat output "\\"))
+          (setq ch #\n))
+        (setq output (concat output (string ch))))
+      (incf index))
+    (concat "\"" output "\"")))
+
+;;; Return T if the string S contains characters which need to be
+;;; escaped to print the symbol name, NIL otherwise.
+(defun escape-symbol-name-p (s)
+  (let ((dots-only t))
+    (dotimes (i (length s))
+      (let ((ch (char s i)))
+        (setf dots-only (and dots-only (char= ch #\.)))
+        (when (or (terminalp ch)
+                  (char= ch #\:)
+                  (char= ch #\\)
+                  (not (char= ch (char-upcase ch)))
+                  (char= ch #\|))
+          (return-from escape-symbol-name-p t))))
+    dots-only))
+
+;;; Return T if the specified string can be read as a number
+;;; In case such a string is the name of a symbol then escaping
+;;; is required when printing to ensure correct reading.
+(defun potential-number-p (string)
+  ;; The four rules for being a potential number are described in
+  ;; 2.3.1.1 Potential Numbers as Token
+  ;;
+  ;; First Rule
+  (dotimes (i (length string))
+    (let ((char (char string i)))
+      (cond
+        ;; Digits TODO: DIGIT-CHAR-P should work with the current
+        ;; radix here. If the radix is not decimal, then we have to
+        ;; make sure there is not a decimal-point in the string.
+        ((digit-char-p char))
+        ;; Signs, ratios, decimal point and extension mark
+        ((find char "+-/._^"))
+        ;; Number marker
+        ((alpha-char-p char)
+         (when (and (< i (1- (length string)))
+                    (alpha-char-p (char string (1+ i))))
+           ;; fail: adjacent letters are not number marker, or
+           ;; there is a decimal point in the string.
+           (return-from potential-number-p)))
+        (t
+         ;; fail: there is a non-allowed character
+         (return-from potential-number-p)))))
+  (and
+   ;; Second Rule. In particular string is not empty.
+   (find-if #'digit-char-p string)
+   ;; Third rule
+   (let ((first (char string 0)))
+     (and (not (char= first #\:))
+          (or (digit-char-p first)
+              (find first "+-._^"))))
+   ;; Fourth rule
+   (not (find (char string (1- (length string))) "+-)"))))
+
+#+nil
+(mapcar #'potential-number-p
+        '("1b5000" "777777q" "1.7J" "-3/4+6.7J" "12/25/83" "27^19"
+          "3^4/5" "6//7" "3.1.2.6" "^-43^" "3.141_592_653_589_793_238_4"
+          "-3.7+2.6i-6.17j+19.6k"))
+
+#+nil
+(mapcar #'potential-number-p '("/" "/5" "+" "1+" "1-" "foo+" "ab.cd" "_" "^" "^/-"))
+
+(defun escape-token-p (string)
+  (or (potential-number-p string)
+      (escape-symbol-name-p string)))
+
+;;; Returns the token in a form that can be used for reading it back.
+(defun escape-token (s)
+  (if (escape-token-p s)
+      (let ((result "|"))
+        (dotimes (i (length s))
+          (let ((ch (char s i)))
+            (when (or (char= ch #\|)
+                      (char= ch #\\))
+              (setf result (concat result "\\")))
+            (setf result (concat result (string ch)))))
+        (concat result "|"))
+      s))
+
+(defvar *print-escape* t)
+(defvar *print-circle* nil)
+
+;;; FIXME: Please, rewrite this in a more organized way.
+(defun write-to-string (form &optional known-objects object-ids)
+  (when (and (not known-objects) *print-circle*)
+    ;; To support *print-circle* some objects must be tracked for
+    ;; sharing: conses, arrays and apparently-uninterned symbols.
+    ;; These objects are placed in an array and a parallel array is
+    ;; used to mark if they're found multiple times by assining them
+    ;; an id starting from 1.
+    ;;
+    ;; After the tracking has been completed the printing phas can
+    ;; begin: if an object has an id > 0 then #<n>= is prefixed and
+    ;; the id is changed to negative. If an object has an id < 0 then
+    ;; #<-n># is printed instead of the object.
+    ;;
+    ;; The processing is O(n^2) with n = number of tracked
+    ;; objects. Hopefully it will become good enough when the new
+    ;; compiler is available.
+    (setf known-objects (make-array 100))
+    (setf object-ids (make-array 100))
+    (let ((n 0)
+          (sz 100)
+          (count 0))
+      (labels ((mark (x)
+                 (let ((i (position x known-objects)))
+                   (if (= i -1)
+                       (progn
+                         (when (= n sz)
+                           (setf sz (* 2 sz))
+                           ;; KLUDGE: storage vectors are an internal
+                           ;; object which the printer should not know
+                           ;; about. Use standard vector with fill
+                           ;; pointers instead.
+                           (resize-storage-vector known-objects sz)
+                           (resize-storage-vector object-ids sz))
+                         (aset known-objects (1- (incf n)) x)
+                         t)
+                       (unless (aref object-ids i)
+                         (aset object-ids i (incf count))
+                         nil))))
+               (visit (x)
+                 (cond
+                   ((and x (symbolp x) (null (symbol-package x)))
+                    (mark x))
+                   ((consp x)
+                    (when (mark x)
+                      (visit (car x))
+                      (visit (cdr x))))
+                   ((vectorp x)
+                    (when (mark x)
+                      (dotimes (i (length x))
+                        (visit (aref x i))))))))
+        (visit form))))
+  (let ((prefix ""))
+    (when (and *print-circle*
+               (or (consp form)
+                   (vectorp form)
+                   (and form (symbolp form) (null (symbol-package form)))))
+      (let* ((ix (position form known-objects))
+             (id (aref object-ids ix)))
+        (cond
+          ((and id (> id 0))
+           (setf prefix (format nil "#~S=" id))
+           (aset object-ids ix (- id)))
+          ((and id (< id 0))
+           (return-from write-to-string (format nil "#~S#" (- id)))))))
+    (concat prefix
+            (cond
+              ((null form) "NIL")
+              ((symbolp form)
+               (let ((name (symbol-name form))
+                     (package (symbol-package form)))
+                 ;; Check if the symbol is accesible from the current package. It
+                 ;; is true even if the symbol's home package is not the current
+                 ;; package, because it could be inherited.
+                 (if (eq form (find-symbol (symbol-name form)))
+                     (escape-token (symbol-name form))
+                     ;; Symbol is not accesible from *PACKAGE*, so let us prefix
+                     ;; the symbol with the optional package or uninterned mark.
+                     (concat (cond
+                               ((null package) "#")
+                               ((eq package (find-package "KEYWORD")) "")
+                               (t (escape-token (package-name package))))
+                             ":"
+                             (if (and package
+                                      (eq (second (multiple-value-list
+                                                      (find-symbol name package)))
+                                          :internal))
+                                 ":"
+                                 "")
+                             (escape-token name)))))
+              ((integerp form) (integer-to-string form))
+              ((floatp form) (float-to-string form))
+              ((characterp form)
+               (concat "#\\"
+                       (case form
+                         (#\newline "newline")
+                         (#\space "space")
+                         (otherwise (string form)))))
+              ((stringp form) (if *print-escape*
+                                  (lisp-escape-string form)
+                                  form))
+              ((functionp form)
+               (let ((name (oget form "fname")))
+                 (if name
+                     (concat "#<FUNCTION " name ">")
+                     (concat "#<FUNCTION>"))))
+              ((listp form)
+               (concat "("
+                       (join-trailing (mapcar (lambda (x)
+                                                (write-to-string x known-objects object-ids))
+                                              (butlast form)) " ")
+                       (let ((last (last form)))
+                         (if (null (cdr last))
+                             (write-to-string (car last) known-objects object-ids)
+                             (concat (write-to-string (car last) known-objects object-ids)
+                                     " . "
+                                     (write-to-string (cdr last) known-objects object-ids))))
+                       ")"))
+              ((vectorp form)
+               (let ((result "#(")
+                     (sep ""))
+                 (dotimes (i (length form))
+                   (setf result (concat result sep
+                                        (write-to-string (aref form i)
+                                                         known-objects
+                                                         object-ids)))
+                   (setf sep " "))
+                 (concat result ")")))
+              ((packagep form)
+               (concat "#<PACKAGE " (package-name form) ">"))
+              (t "#<javascript object>")))))
+
 (defun prin1-to-string (form)
-  (cond
-    ((symbolp form)
-     (multiple-value-bind (symbol foundp)
-         (find-symbol (symbol-name form) *package*)
-       (if (and foundp (eq symbol form))
-           (symbol-name form)
-           (let ((package (symbol-package form))
-                 (name (symbol-name form)))
-             (concat (cond
-                       ((null package) "#")
-                       ((eq package (find-package "KEYWORD")) "")
-                       (t (package-name package)))
-                     ":" name)))))
-    ((integerp form) (integer-to-string form))
-    ((floatp form) (float-to-string form))
-    ((stringp form) (concat "\"" (escape-string form) "\""))
-    ((functionp form)
-     (let ((name (oget form "fname")))
-       (if name
-           (concat "#<FUNCTION " name ">")
-           (concat "#<FUNCTION>"))))
-    ((listp form)
-     (concat "("
-             (join-trailing (mapcar #'prin1-to-string (butlast form)) " ")
-             (let ((last (last form)))
-               (if (null (cdr last))
-                   (prin1-to-string (car last))
-                   (concat (prin1-to-string (car last)) " . " (prin1-to-string (cdr last)))))
-             ")"))
-    ((arrayp form)
-     (concat "#" (if (zerop (length form))
-                     "()"
-                     (prin1-to-string (vector-to-list form)))))
-    ((packagep form)
-     (concat "#<PACKAGE " (package-name form) ">"))
-    (t
-     (concat "#<javascript object>"))))
+  (let ((*print-escape* t))
+    (write-to-string form)))
+
+(defun princ-to-string (form)
+  (let ((*print-escape* nil))
+    (write-to-string form)))
+
+(defun terpri ()
+  (write-char #\newline)
+  (values))
 
 (defun write-line (x)
   (write-string x)
-  (write-string *newline*)
+  (terpri)
   x)
 
-(defun warn (string)
+(defun warn (fmt &rest args)
   (write-string "WARNING: ")
-  (write-line string))
+  (apply #'format t fmt args)
+  (terpri))
 
 (defun print (x)
   (write-line (prin1-to-string x))
   x)
+
+(defun format (destination fmt &rest args)
+  (let ((len (length fmt))
+        (i 0)
+        (res "")
+        (arguments args))
+    (while (< i len)
+      (let ((c (char fmt i)))
+        (if (char= c #\~)
+            (let ((next (char fmt (incf i))))
+              (cond
+               ((char= next #\~)
+                (concatf res "~"))
+               ((char= next #\%)
+                (concatf res (string #\newline)))
+               ((char= next #\*)
+                (pop arguments))
+               (t
+                (concatf res (format-special next (car arguments)))
+                (pop arguments))))
+            (setq res (concat res (string c))))
+        (incf i)))
+    (if destination
+        (progn
+          (write-string res)
+          nil)
+        res)))
+
+(defun format-special (chr arg)
+  (case (char-upcase chr)
+    (#\S (prin1-to-string arg))
+    (#\A (princ-to-string arg))
+    (#\D (princ-to-string arg))
+    (t
+     (warn "~S is not implemented yet, using ~~S instead" chr)
+     (prin1-to-string arg))))