X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Freader.lisp;h=f4352e68945f50cdd298bc5b72c6178d69166dc0;hb=cb296ae5a022a5b0f1fd573584301b0d2a9493f9;hp=69d1a6f9df0da2b50e3a2c486ddb99aefab03575;hpb=c713eb2b521b048ff2c927ec52b861787d289f85;p=sbcl.git

diff --git a/src/code/reader.lisp b/src/code/reader.lisp
index 69d1a6f..f4352e6 100644
--- a/src/code/reader.lisp
+++ b/src/code/reader.lisp
@@ -61,24 +61,46 @@
 (defmacro get-cat-entry (char rt)
   ;; KLUDGE: Only give this side-effect-free args.
   ;; FIXME: should probably become inline function
-  `(elt (character-attribute-table ,rt)
-	(char-code ,char)))
+  `(if (typep ,char 'base-char)
+       (elt (character-attribute-array ,rt) (char-code ,char))
+       (gethash ,char (character-attribute-hash-table ,rt) +char-attr-constituent+)))
 
 (defun set-cat-entry (char newvalue &optional (rt *readtable*))
-  (setf (elt (character-attribute-table rt)
-	     (char-code char))
-	newvalue))
-
-;;; FIXME: could be SB!XC:DEFMACRO inside EVAL-WHEN (COMPILE EVAL)
-(defmacro get-cmt-entry (char rt)
-  `(the function
-	(elt (the simple-vector (character-macro-table ,rt))
-	     (char-code ,char))))
-
-(defun set-cmt-entry (char newvalue &optional (rt *readtable*))
-  (setf (elt (the simple-vector (character-macro-table rt))
-	     (char-code char))
-	(coerce newvalue 'function)))
+  (if (typep char 'base-char)
+      (setf (elt (character-attribute-array rt) (char-code char)) newvalue)
+      ;; FIXME: could REMHASH if we're setting to
+      ;; +CHAR-ATTR-CONSTITUENT+
+      (setf (gethash char (character-attribute-hash-table rt)) newvalue)))
+
+;;; the value actually stored in the character macro table. As per
+;;; ANSI #'GET-MACRO-CHARACTER and #'SET-MACRO-CHARACTER, this can
+;;; be either a function or NIL.
+(eval-when (:compile-toplevel :execute)
+  (sb!xc:defmacro get-raw-cmt-entry (char readtable)
+    `(if (typep ,char 'base-char)
+         (svref (character-macro-array ,readtable) (char-code ,char))
+         ;; Note: DEFAULT here is NIL, not #'UNDEFINED-MACRO-CHAR, so
+         ;; that everything above the base-char range is a non-macro
+         ;; constituent by default.
+         (gethash ,char (character-macro-hash-table ,readtable) nil))))
+
+;;; the value represented by whatever is stored in the character macro
+;;; table. As per ANSI #'GET-MACRO-CHARACTER and #'SET-MACRO-CHARACTER,
+;;; a function value represents itself, and a NIL value represents the
+;;; default behavior.
+(defun get-coerced-cmt-entry (char readtable)
+  (the function 
+    (or (get-raw-cmt-entry char readtable)
+	#'read-token)))
+
+(defun set-cmt-entry (char new-value-designator &optional (rt *readtable*))
+  (if (typep char 'base-char)
+      (setf (svref (character-macro-array rt) (char-code char))
+            (and new-value-designator
+                 (%coerce-callable-to-fun new-value-designator)))
+      (setf (gethash char (character-macro-hash-table rt))
+	(and new-value-designator
+                 (%coerce-callable-to-fun new-value-designator)))))
 
 (defun undefined-macro-char (stream char)
   (unless *read-suppress*
@@ -125,7 +147,7 @@
 
 (defun !cold-init-secondary-attribute-table ()
   (setq *secondary-attribute-table*
-	(make-array char-code-limit :element-type '(unsigned-byte 8)
+	(make-array base-char-code-limit :element-type '(unsigned-byte 8)
 		    :initial-element +char-attr-constituent+))
   (!set-secondary-attribute #\: +char-attr-package-delimiter+)
   (!set-secondary-attribute #\| +char-attr-multiple-escape+) ; |) [for EMACS]
@@ -153,17 +175,29 @@
 
 ;;;; readtable operations
 
+(defun shallow-replace/eql-hash-table (to from)
+  (maphash (lambda (k v) (setf (gethash k to) v)) from))
+
 (defun copy-readtable (&optional (from-readtable *readtable*)
 				 to-readtable)
   (let ((really-from-readtable (or from-readtable *standard-readtable*))
         (really-to-readtable (or to-readtable (make-readtable))))
-    (replace (character-attribute-table really-to-readtable)
-	     (character-attribute-table really-from-readtable))
-    (replace (character-macro-table really-to-readtable)
-	     (character-macro-table really-from-readtable))
+    (replace (character-attribute-array really-to-readtable)
+	     (character-attribute-array really-from-readtable))
+    (shallow-replace/eql-hash-table
+     (character-attribute-hash-table really-to-readtable)
+     (character-attribute-hash-table really-from-readtable))
+    (replace (character-macro-array really-to-readtable)
+	     (character-macro-array really-from-readtable))
+    (shallow-replace/eql-hash-table
+     (character-macro-hash-table really-to-readtable)
+     (character-macro-hash-table really-from-readtable))
     (setf (dispatch-tables really-to-readtable)
-	  (mapcar (lambda (pair) (cons (car pair)
-				       (copy-seq (cdr pair))))
+	  (mapcar (lambda (pair)
+                    (cons (car pair)
+                          (let ((table (make-hash-table)))
+                            (shallow-replace/eql-hash-table table (cdr pair))
+                            table)))
 		  (dispatch-tables really-from-readtable)))
     (setf (readtable-case really-to-readtable)
 	  (readtable-case really-from-readtable))
@@ -178,7 +212,7 @@
   FROM-TABLE defaults to the standard Lisp readtable when NIL."
   (let ((really-from-readtable (or from-readtable *standard-readtable*)))
     ;; Copy FROM-CHAR entries to TO-CHAR entries, but make sure that if
-    ;; from char is a constituent you don't copy non-movable secondary
+    ;; FROM-CHAR is a constituent you don't copy non-movable secondary
     ;; attributes (constituent types), and that said attributes magically
     ;; appear if you transform a non-constituent to a constituent.
     (let ((att (get-cat-entry from-char really-from-readtable)))
@@ -186,42 +220,51 @@
 	  (setq att (get-secondary-attribute to-char)))
       (set-cat-entry to-char att to-readtable)
       (set-cmt-entry to-char
-		     (get-cmt-entry from-char really-from-readtable)
+		     (get-raw-cmt-entry from-char really-from-readtable)
 		     to-readtable)))
   t)
 
 (defun set-macro-character (char function &optional
-				 (non-terminatingp nil) (rt *readtable*))
+				 (non-terminatingp nil)
+				 (readtable *readtable*))
   #!+sb-doc
-  "Causes CHAR to be a macro character which invokes FUNCTION when
-   seen by the reader. The NON-TERMINATINGP flag can be used to
-   make the macro character non-terminating. The optional readtable
-   argument defaults to the current readtable. SET-MACRO-CHARACTER
-   returns T."
-  (let ((rt (or rt *standard-readtable*)))
-    (if non-terminatingp
-        (set-cat-entry char (get-secondary-attribute char) rt)
-        (set-cat-entry char +char-attr-terminating-macro+ rt))
-    (set-cmt-entry char function rt)
-    T))
-
-(defun get-macro-character (char &optional (rt *readtable*))
+  "Causes CHAR to be a macro character which invokes FUNCTION when seen
+   by the reader. The NON-TERMINATINGP flag can be used to make the macro
+   character non-terminating, i.e. embeddable in a symbol name."
+  (let ((designated-readtable (or readtable *standard-readtable*)))
+    (set-cat-entry char
+		   (if non-terminatingp
+		       (get-secondary-attribute char)
+		       +char-attr-terminating-macro+)
+		   designated-readtable)
+    (set-cmt-entry char function designated-readtable)
+    t)) ; (ANSI-specified return value)
+
+(defun get-macro-character (char &optional (readtable *readtable*))
   #!+sb-doc
   "Return the function associated with the specified CHAR which is a macro
-  character. The optional readtable argument defaults to the current
-  readtable."
-  (let ((rt (or rt *standard-readtable*)))
-    ;; Check macro syntax, return associated function if it's there.
-    ;; Returns a value for all constituents.
-    (cond ((constituentp char)
-	   (values (get-cmt-entry char rt) t))
-	  ((terminating-macrop char)
-	   (values (get-cmt-entry char rt) nil))
-	  (t nil))))
+  character, or NIL if there is no such function. As a second value, return
+  T if CHAR is a macro character which is non-terminating, i.e. which can
+  be embedded in a symbol name."
+  (let* ((designated-readtable (or readtable *standard-readtable*))
+	 ;; the first return value: a FUNCTION if CHAR is a macro
+	 ;; character, or NIL otherwise
+	 (fun-value (get-raw-cmt-entry char designated-readtable)))
+    (values fun-value
+	    ;; NON-TERMINATING-P return value:
+	    (if fun-value
+		(or (constituentp char)
+		    (not (terminating-macrop char)))
+		;; ANSI's definition of GET-MACRO-CHARACTER says this
+		;; value is NIL when CHAR is not a macro character.
+		;; I.e. this value means not just "non-terminating
+		;; character?" but "non-terminating macro character?".
+		nil))))
 
 ;;;; definitions to support internal programming conventions
 
-(defmacro eofp (char) `(eq ,char *eof-object*))
+(defmacro eofp (char)
+  `(eq ,char *eof-object*))
 
 (defun flush-whitespace (stream)
   ;; This flushes whitespace chars, returning the last char it read (a
@@ -229,17 +272,27 @@
   (let ((stream (in-synonym-of stream)))
     (if (ansi-stream-p stream)
 	(prepare-for-fast-read-char stream
-	  (do ((attribute-table (character-attribute-table *readtable*))
+	  (do ((attribute-array (character-attribute-array *readtable*))
+               (attribute-hash-table
+                (character-attribute-hash-table *readtable*))
 	       (char (fast-read-char t) (fast-read-char t)))
-	      ((/= (the fixnum (aref attribute-table (char-code char)))
+	      ((/= (the fixnum
+                     (if (typep char 'base-char)
+                         (aref attribute-array (char-code char))
+                         (gethash char attribute-hash-table +char-attr-constituent+)))
 		   +char-attr-whitespace+)
 	       (done-with-fast-read-char)
 	       char)))
-	;; fundamental-stream
-	(do ((attribute-table (character-attribute-table *readtable*))
-	     (char (stream-read-char stream) (stream-read-char stream)))
+	;; CLOS stream
+	(do ((attribute-array (character-attribute-array *readtable*))
+             (attribute-hash-table
+              (character-attribute-hash-table *readtable*))
+	     (char (read-char stream nil :eof) (read-char stream nil :eof)))
 	    ((or (eq char :eof)
-		 (/= (the fixnum (aref attribute-table (char-code char)))
+		 (/= (the fixnum
+                       (if (typep char 'base-char)
+                           (aref attribute-array (char-code char))
+                           (gethash char attribute-hash-table +char-attr-constituent+)))
 		     +char-attr-whitespace+))
 	     (if (eq char :eof)
 		 (error 'end-of-file :stream stream)
@@ -249,35 +302,40 @@
 
 (defun !cold-init-standard-readtable ()
   (setq *standard-readtable* (make-readtable))
-  ;; All characters default to "constituent" in MAKE-READTABLE.
-  ;; *** un-constituent-ize some of these ***
+  ;; All characters get boring defaults in MAKE-READTABLE. Now we
+  ;; override the boring defaults on characters which need more
+  ;; interesting behavior.
   (let ((*readtable* *standard-readtable*))
-    (set-cat-entry (code-char tab-char-code) +char-attr-whitespace+)
-    (set-cat-entry #\linefeed +char-attr-whitespace+)
-    (set-cat-entry #\space +char-attr-whitespace+)
-    (set-cat-entry (code-char form-feed-char-code) +char-attr-whitespace+)
-    (set-cat-entry (code-char return-char-code) +char-attr-whitespace+)
+
+    (flet ((whitespaceify (char)
+	     (set-cmt-entry char nil)
+	     (set-cat-entry char +char-attr-whitespace+)))
+      (whitespaceify (code-char tab-char-code))
+      (whitespaceify #\linefeed)
+      (whitespaceify #\space)
+      (whitespaceify (code-char form-feed-char-code))
+      (whitespaceify (code-char return-char-code)))
+
     (set-cat-entry #\\ +char-attr-escape+)
-    (set-cmt-entry #\\ #'read-token)
-    (set-cat-entry (code-char rubout-char-code) +char-attr-whitespace+)
-    (set-cmt-entry #\: #'read-token)
-    (set-cmt-entry #\| #'read-token)
-    ;; macro definitions
+    (set-cmt-entry #\\ nil)
+
+    ;; Easy macro-character definitions are in this source file.
     (set-macro-character #\" #'read-string)
-    ;; * # macro
     (set-macro-character #\' #'read-quote)
     (set-macro-character #\( #'read-list)
     (set-macro-character #\) #'read-right-paren)
     (set-macro-character #\; #'read-comment)
-    ;; * backquote
+    ;; (The hairier macro-character definitions, for #\# and #\`, are
+    ;; defined elsewhere, in their own source files.)
+
     ;; all constituents
     (do ((ichar 0 (1+ ichar))
 	 (char))
-	((= ichar #O200))
+	((= ichar base-char-code-limit))
       (setq char (code-char ichar))
       (when (constituentp char *standard-readtable*)
-	    (set-cat-entry char (get-secondary-attribute char))
-	    (set-cmt-entry char #'read-token)))))
+	(set-cat-entry char (get-secondary-attribute char))
+	(set-cmt-entry char nil)))))
 
 ;;;; implementation of the read buffer
 
@@ -291,7 +349,7 @@
 (defvar *ouch-ptr*)
 
 (declaim (type index *read-buffer-length* *inch-ptr* *ouch-ptr*))
-(declaim (simple-string *read-buffer*))
+(declaim (type (simple-array character (*)) *read-buffer*))
 
 (defmacro reset-read-buffer ()
   ;; Turn *READ-BUFFER* into an empty read buffer.
@@ -381,18 +439,19 @@
   "Read from STREAM and return the value read, preserving any whitespace
    that followed the object."
   (if recursivep
-    ;; a loop for repeating when a macro returns nothing
-    (loop
-      (let ((char (read-char stream eof-error-p *eof-object*)))
-	(cond ((eofp char) (return eof-value))
-	      ((whitespacep char))
-	      (t
-	       (let* ((macrofun (get-cmt-entry char *readtable*))
-		      (result (multiple-value-list
-			       (funcall macrofun stream char))))
-		 ;; Repeat if macro returned nothing.
-		  (if result (return (car result))))))))
-    (let ((*sharp-equal-alist* nil))
+      ;; a loop for repeating when a macro returns nothing
+      (loop
+       (let ((char (read-char stream eof-error-p *eof-object*)))
+         (cond ((eofp char) (return eof-value))
+               ((whitespacep char))
+               (t
+                (let* ((macrofun (get-coerced-cmt-entry char *readtable*))
+                       (result (multiple-value-list
+                                (funcall macrofun stream char))))
+                  ;; Repeat if macro returned nothing.
+		  (when result 
+                    (return (unless *read-suppress* (car result)))))))))
+      (let ((*sharp-equal-alist* nil))
 	(read-preserving-whitespace stream eof-error-p eof-value t))))
 
 ;;; Return NIL or a list with one thing, depending.
@@ -401,7 +460,9 @@
 ;;; past them. We assume CHAR is not whitespace.
 (defun read-maybe-nothing (stream char)
   (let ((retval (multiple-value-list
-		 (funcall (get-cmt-entry char *readtable*) stream char))))
+		 (funcall (get-coerced-cmt-entry char *readtable*)
+			  stream
+			  char))))
     (if retval (rplacd retval nil))))
 
 (defun read (&optional (stream *standard-input*)
@@ -414,9 +475,9 @@
 					    eof-error-p
 					    eof-value
 					    recursivep)))
-    ;; (This function generally discards trailing whitespace. If you
+    ;; This function generally discards trailing whitespace. If you
     ;; don't want to discard trailing whitespace, call
-    ;; CL:READ-PRESERVING-WHITESPACE instead.)
+    ;; CL:READ-PRESERVING-WHITESPACE instead.
     (unless (or (eql result eof-value) recursivep)
       (let ((next-char (read-char stream nil nil)))
 	(unless (or (null next-char)
@@ -435,7 +496,7 @@
   (do ((char (flush-whitespace input-stream)
 	     (flush-whitespace input-stream))
        (retlist ()))
-      ((char= char endchar) (nreverse retlist))
+      ((char= char endchar) (unless *read-suppress* (nreverse retlist)))
     (setq retlist (nconc (read-maybe-nothing input-stream char) retlist))))
 
 ;;;; basic readmacro definitions
@@ -456,8 +517,8 @@
 		     (fast-read-char nil nil)))
 	      ((or (not char) (char= char #\newline))
 	       (done-with-fast-read-char))))
-	;; FUNDAMENTAL-STREAM
-	(do ((char (stream-read-char stream) (stream-read-char stream)))
+	;; CLOS stream
+	(do ((char (read-char stream nil :eof) (read-char stream nil :eof)))
 	    ((or (eq char :eof) (char= char #\newline))))))
   ;; Don't return anything.
   (values))
@@ -520,13 +581,13 @@
 	       (done-with-fast-read-char))
 	    (if (escapep char) (setq char (fast-read-char t)))
 	    (ouch-read-buffer char)))
-	;; FUNDAMENTAL-STREAM
-	(do ((char (stream-read-char stream) (stream-read-char stream)))
+	;; CLOS stream
+	(do ((char (read-char stream nil :eof) (read-char stream nil :eof)))
 	    ((or (eq char :eof) (char= char closech))
 	     (if (eq char :eof)
 		 (error 'end-of-file :stream stream)))
 	  (when (escapep char)
-	    (setq char (stream-read-char stream))
+	    (setq char (read-char stream nil :eof))
 	    (if (eq char :eof)
 		(error 'end-of-file :stream stream)))
 	  (ouch-read-buffer char))))
@@ -593,8 +654,13 @@
 ;;;; character classes
 
 ;;; Return the character class for CHAR.
-(defmacro char-class (char attable)
-  `(let ((att (aref ,attable (char-code ,char))))
+;;;
+;;; FIXME: why aren't these ATT-getting forms using GET-CAT-ENTRY?
+;;; Because we've cached the readtable tables?
+(defmacro char-class (char attarray atthash)
+  `(let ((att (if (typep ,char 'base-char)
+                  (aref ,attarray (char-code ,char))
+                  (gethash ,char ,atthash +char-attr-constituent+))))
      (declare (fixnum att))
      (if (<= att +char-attr-terminating-macro+)
 	 +char-attr-delimiter+
@@ -602,8 +668,10 @@
 
 ;;; Return the character class for CHAR, which might be part of a
 ;;; rational number.
-(defmacro char-class2 (char attable)
-  `(let ((att (aref ,attable (char-code ,char))))
+(defmacro char-class2 (char attarray atthash)
+  `(let ((att (if (typep ,char 'base-char)
+                  (aref ,attarray (char-code ,char))
+                  (gethash ,char ,atthash +char-attr-constituent+))))
      (declare (fixnum att))
      (if (<= att +char-attr-terminating-macro+)
 	 +char-attr-delimiter+
@@ -616,8 +684,10 @@
 ;;; Return the character class for a char which might be part of a
 ;;; rational or floating number. (Assume that it is a digit if it
 ;;; could be.)
-(defmacro char-class3 (char attable)
-  `(let ((att (aref ,attable (char-code ,char))))
+(defmacro char-class3 (char attarray atthash)
+  `(let ((att (if (typep ,char 'base-char)
+                  (aref ,attarray (char-code ,char))
+                  (gethash ,char ,atthash +char-attr-constituent+))))
      (declare (fixnum att))
      (if possibly-rational
 	 (setq possibly-rational
@@ -631,8 +701,10 @@
 	 +char-attr-delimiter+
 	 (if (digit-char-p ,char (max *read-base* 10))
 	     (if (digit-char-p ,char *read-base*)
-		 +char-attr-constituent-digit+
-		 +char-attr-constituent+)
+		 (if (= att +char-attr-constituent-expt+)
+		     +char-attr-constituent-digit-or-expt+
+		     +char-attr-constituent-digit+)
+		 +char-attr-constituent-decimal-digit+)
 	     att))))
 
 ;;;; token fetching
@@ -704,17 +776,25 @@
   (when *read-suppress*
     (internal-read-extended-token stream firstchar nil)
     (return-from read-token nil))
-  (let ((attribute-table (character-attribute-table *readtable*))
+  (let ((attribute-array (character-attribute-array *readtable*))
+        (attribute-hash-table (character-attribute-hash-table *readtable*))
 	(package-designator nil)
 	(colons 0)
 	(possibly-rational t)
+	(seen-digit-or-expt nil)
 	(possibly-float t)
-	(escapes ()))
+	(was-possibly-float nil)
+	(escapes ())
+	(seen-multiple-escapes nil))
     (reset-read-buffer)
     (prog ((char firstchar))
-      (case (char-class3 char attribute-table)
+      (case (char-class3 char attribute-array attribute-hash-table)
 	(#.+char-attr-constituent-sign+ (go SIGN))
 	(#.+char-attr-constituent-digit+ (go LEFTDIGIT))
+	(#.+char-attr-constituent-digit-or-expt+
+	 (setq seen-digit-or-expt t)
+	 (go LEFTDIGIT))
+	(#.+char-attr-constituent-decimal-digit+ (go LEFTDECIMALDIGIT))
 	(#.+char-attr-constituent-dot+ (go FRONTDOT))
 	(#.+char-attr-escape+ (go ESCAPE))
 	(#.+char-attr-package-delimiter+ (go COLON))
@@ -727,8 +807,12 @@
       (unless char (go RETURN-SYMBOL))
       (setq possibly-rational t
 	    possibly-float t)
-      (case (char-class3 char attribute-table)
+      (case (char-class3 char attribute-array attribute-hash-table)
 	(#.+char-attr-constituent-digit+ (go LEFTDIGIT))
+	(#.+char-attr-constituent-digit-or-expt+
+	 (setq seen-digit-or-expt t)
+	 (go LEFTDIGIT))
+	(#.+char-attr-constituent-decimal-digit+ (go LEFTDECIMALDIGIT))
 	(#.+char-attr-constituent-dot+ (go SIGNDOT))
 	(#.+char-attr-escape+ (go ESCAPE))
 	(#.+char-attr-package-delimiter+ (go COLON))
@@ -739,12 +823,43 @@
       (ouch-read-buffer char)
       (setq char (read-char stream nil nil))
       (unless char (return (make-integer)))
-      (case (char-class3 char attribute-table)
+      (setq was-possibly-float possibly-float)
+      (case (char-class3 char attribute-array attribute-hash-table)
 	(#.+char-attr-constituent-digit+ (go LEFTDIGIT))
+	(#.+char-attr-constituent-decimal-digit+ (if possibly-float
+						     (go LEFTDECIMALDIGIT)
+						     (go SYMBOL)))
 	(#.+char-attr-constituent-dot+ (if possibly-float
 					   (go MIDDLEDOT)
 					   (go SYMBOL)))
-	(#.+char-attr-constituent-expt+ (go EXPONENT))
+	(#.+char-attr-constituent-digit-or-expt+
+	 (if (or seen-digit-or-expt (not was-possibly-float))
+	     (progn (setq seen-digit-or-expt t) (go LEFTDIGIT))
+	     (progn (setq seen-digit-or-expt t) (go LEFTDIGIT-OR-EXPT))))
+	(#.+char-attr-constituent-expt+
+	 (if was-possibly-float
+	     (go EXPONENT)
+	     (go SYMBOL)))
+	(#.+char-attr-constituent-slash+ (if possibly-rational
+					     (go RATIO)
+					     (go SYMBOL)))
+	(#.+char-attr-delimiter+ (unread-char char stream)
+				 (return (make-integer)))
+	(#.+char-attr-escape+ (go ESCAPE))
+	(#.+char-attr-multiple-escape+ (go MULT-ESCAPE))
+	(#.+char-attr-package-delimiter+ (go COLON))
+	(t (go SYMBOL)))
+     LEFTDIGIT-OR-EXPT
+      (ouch-read-buffer char)
+      (setq char (read-char stream nil nil))
+      (unless char (return (make-integer)))
+      (case (char-class3 char attribute-array attribute-hash-table)
+	(#.+char-attr-constituent-digit+ (go LEFTDIGIT))
+	(#.+char-attr-constituent-decimal-digit+ (bug "impossible!"))
+	(#.+char-attr-constituent-dot+ (go SYMBOL))
+	(#.+char-attr-constituent-digit-or-expt+ (go LEFTDIGIT))
+	(#.+char-attr-constituent-expt+ (go SYMBOL))
+	(#.+char-attr-constituent-sign+ (go EXPTSIGN))
 	(#.+char-attr-constituent-slash+ (if possibly-rational
 					     (go RATIO)
 					     (go SYMBOL)))
@@ -754,12 +869,29 @@
 	(#.+char-attr-multiple-escape+ (go MULT-ESCAPE))
 	(#.+char-attr-package-delimiter+ (go COLON))
 	(t (go SYMBOL)))
+     LEFTDECIMALDIGIT ; saw "[sign] {decimal-digit}+"
+      (aver possibly-float)
+      (ouch-read-buffer char)
+      (setq char (read-char stream nil nil))
+      (unless char (go RETURN-SYMBOL))
+      (case (char-class char attribute-array attribute-hash-table)
+	(#.+char-attr-constituent-digit+ (go LEFTDECIMALDIGIT))
+	(#.+char-attr-constituent-dot+ (go MIDDLEDOT))
+	(#.+char-attr-constituent-expt+ (go EXPONENT))
+	(#.+char-attr-constituent-slash+ (aver (not possibly-rational))
+					 (go SYMBOL))
+	(#.+char-attr-delimiter+ (unread-char char stream)
+				 (go RETURN-SYMBOL))
+	(#.+char-attr-escape+ (go ESCAPE))
+	(#.+char-attr-multiple-escape+ (go MULT-ESCAPE))
+	(#.+char-attr-package-delimiter+ (go COLON))
+	(t (go SYMBOL)))
      MIDDLEDOT ; saw "[sign] {digit}+ dot"
       (ouch-read-buffer char)
       (setq char (read-char stream nil nil))
       (unless char (return (let ((*read-base* 10))
 			     (make-integer))))
-      (case (char-class char attribute-table)
+      (case (char-class char attribute-array attribute-hash-table)
 	(#.+char-attr-constituent-digit+ (go RIGHTDIGIT))
 	(#.+char-attr-constituent-expt+ (go EXPONENT))
 	(#.+char-attr-delimiter+
@@ -770,16 +902,16 @@
 	(#.+char-attr-multiple-escape+ (go MULT-ESCAPE))
 	(#.+char-attr-package-delimiter+ (go COLON))
 	(t (go SYMBOL)))
-     RIGHTDIGIT ; saw "[sign] {digit}* dot {digit}+"
+     RIGHTDIGIT ; saw "[sign] {decimal-digit}* dot {digit}+"
       (ouch-read-buffer char)
       (setq char (read-char stream nil nil))
-      (unless char (return (make-float)))
-      (case (char-class char attribute-table)
+      (unless char (return (make-float stream)))
+      (case (char-class char attribute-array attribute-hash-table)
 	(#.+char-attr-constituent-digit+ (go RIGHTDIGIT))
 	(#.+char-attr-constituent-expt+ (go EXPONENT))
 	(#.+char-attr-delimiter+
 	 (unread-char char stream)
-	 (return (make-float)))
+	 (return (make-float stream)))
 	(#.+char-attr-escape+ (go ESCAPE))
 	(#.+char-attr-multiple-escape+ (go MULT-ESCAPE))
 	(#.+char-attr-package-delimiter+ (go COLON))
@@ -788,7 +920,7 @@
       (ouch-read-buffer char)
       (setq char (read-char stream nil nil))
       (unless char (go RETURN-SYMBOL))
-      (case (char-class char attribute-table)
+      (case (char-class char attribute-array attribute-hash-table)
 	(#.+char-attr-constituent-digit+ (go RIGHTDIGIT))
 	(#.+char-attr-delimiter+ (unread-char char stream) (go RETURN-SYMBOL))
 	(#.+char-attr-escape+ (go ESCAPE))
@@ -798,7 +930,7 @@
       (ouch-read-buffer char)
       (setq char (read-char stream nil nil))
       (unless char (%reader-error stream "dot context error"))
-      (case (char-class char attribute-table)
+      (case (char-class char attribute-array attribute-hash-table)
 	(#.+char-attr-constituent-digit+ (go RIGHTDIGIT))
 	(#.+char-attr-constituent-dot+ (go DOTS))
 	(#.+char-attr-delimiter+  (%reader-error stream "dot context error"))
@@ -810,7 +942,8 @@
       (ouch-read-buffer char)
       (setq char (read-char stream nil nil))
       (unless char (go RETURN-SYMBOL))
-      (case (char-class char attribute-table)
+      (setq possibly-float t)
+      (case (char-class char attribute-array attribute-hash-table)
 	(#.+char-attr-constituent-sign+ (go EXPTSIGN))
 	(#.+char-attr-constituent-digit+ (go EXPTDIGIT))
 	(#.+char-attr-delimiter+ (unread-char char stream) (go RETURN-SYMBOL))
@@ -822,7 +955,7 @@
       (ouch-read-buffer char)
       (setq char (read-char stream nil nil))
       (unless char (go RETURN-SYMBOL))
-      (case (char-class char attribute-table)
+      (case (char-class char attribute-array attribute-hash-table)
 	(#.+char-attr-constituent-digit+ (go EXPTDIGIT))
 	(#.+char-attr-delimiter+ (unread-char char stream) (go RETURN-SYMBOL))
 	(#.+char-attr-escape+ (go ESCAPE))
@@ -832,12 +965,12 @@
      EXPTDIGIT ; got to EXPONENT, saw "[sign] {digit}+"
       (ouch-read-buffer char)
       (setq char (read-char stream nil nil))
-      (unless char (return (make-float)))
-      (case (char-class char attribute-table)
+      (unless char (return (make-float stream)))
+      (case (char-class char attribute-array attribute-hash-table)
 	(#.+char-attr-constituent-digit+ (go EXPTDIGIT))
 	(#.+char-attr-delimiter+
 	 (unread-char char stream)
-	 (return (make-float)))
+	 (return (make-float stream)))
 	(#.+char-attr-escape+ (go ESCAPE))
 	(#.+char-attr-multiple-escape+ (go MULT-ESCAPE))
 	(#.+char-attr-package-delimiter+ (go COLON))
@@ -846,7 +979,7 @@
       (ouch-read-buffer char)
       (setq char (read-char stream nil nil))
       (unless char (go RETURN-SYMBOL))
-      (case (char-class2 char attribute-table)
+      (case (char-class2 char attribute-array attribute-hash-table)
 	(#.+char-attr-constituent-digit+ (go RATIODIGIT))
 	(#.+char-attr-delimiter+ (unread-char char stream) (go RETURN-SYMBOL))
 	(#.+char-attr-escape+ (go ESCAPE))
@@ -856,12 +989,12 @@
      RATIODIGIT ; saw "[sign] {digit}+ slash {digit}+"
       (ouch-read-buffer char)
       (setq char (read-char stream nil nil))
-      (unless char (return (make-ratio)))
-      (case (char-class2 char attribute-table)
+      (unless char (return (make-ratio stream)))
+      (case (char-class2 char attribute-array attribute-hash-table)
 	(#.+char-attr-constituent-digit+ (go RATIODIGIT))
 	(#.+char-attr-delimiter+
 	 (unread-char char stream)
-	 (return (make-ratio)))
+	 (return (make-ratio stream)))
 	(#.+char-attr-escape+ (go ESCAPE))
 	(#.+char-attr-multiple-escape+ (go MULT-ESCAPE))
 	(#.+char-attr-package-delimiter+ (go COLON))
@@ -870,7 +1003,7 @@
       (ouch-read-buffer char)
       (setq char (read-char stream nil nil))
       (unless char (%reader-error stream "too many dots"))
-      (case (char-class char attribute-table)
+      (case (char-class char attribute-array attribute-hash-table)
 	(#.+char-attr-constituent-dot+ (go DOTS))
 	(#.+char-attr-delimiter+
 	 (unread-char char stream)
@@ -888,7 +1021,7 @@
 	       (ouch-read-buffer char)
 	       (setq char (fast-read-char nil nil))
 	       (unless char (go RETURN-SYMBOL))
-	       (case (char-class char attribute-table)
+	       (case (char-class char attribute-array attribute-hash-table)
 		 (#.+char-attr-escape+ (done-with-fast-read-char)
 				       (go ESCAPE))
 		 (#.+char-attr-delimiter+ (done-with-fast-read-char)
@@ -899,15 +1032,15 @@
 		 (#.+char-attr-package-delimiter+ (done-with-fast-read-char)
 						  (go COLON))
 		 (t (go SYMBOL-LOOP)))))
-	    ;; fundamental-stream
+	    ;; CLOS stream
 	    (prog ()
 	     SYMBOL-LOOP
 	     (ouch-read-buffer char)
-	     (setq char (stream-read-char stream))
+	     (setq char (read-char stream nil :eof))
 	     (when (eq char :eof) (go RETURN-SYMBOL))
-	     (case (char-class char attribute-table)
+	     (case (char-class char attribute-array attribute-hash-table)
 	       (#.+char-attr-escape+ (go ESCAPE))
-	       (#.+char-attr-delimiter+ (stream-unread-char stream char)
+	       (#.+char-attr-delimiter+ (unread-char char stream)
 			    (go RETURN-SYMBOL))
 	       (#.+char-attr-multiple-escape+ (go MULT-ESCAPE))
 	       (#.+char-attr-package-delimiter+ (go COLON))
@@ -922,13 +1055,14 @@
 	(ouch-read-buffer nextchar))
       (setq char (read-char stream nil nil))
       (unless char (go RETURN-SYMBOL))
-      (case (char-class char attribute-table)
+      (case (char-class char attribute-array attribute-hash-table)
 	(#.+char-attr-delimiter+ (unread-char char stream) (go RETURN-SYMBOL))
 	(#.+char-attr-escape+ (go ESCAPE))
 	(#.+char-attr-multiple-escape+ (go MULT-ESCAPE))
 	(#.+char-attr-package-delimiter+ (go COLON))
 	(t (go SYMBOL)))
       MULT-ESCAPE
+      (setq seen-multiple-escapes t)
       (do ((char (read-char stream t) (read-char stream t)))
 	  ((multiple-escape-p char))
 	(if (escapep char) (setq char (read-char stream t)))
@@ -936,7 +1070,7 @@
 	(ouch-read-buffer char))
       (setq char (read-char stream nil nil))
       (unless char (go RETURN-SYMBOL))
-      (case (char-class char attribute-table)
+      (case (char-class char attribute-array attribute-hash-table)
 	(#.+char-attr-delimiter+ (unread-char char stream) (go RETURN-SYMBOL))
 	(#.+char-attr-escape+ (go ESCAPE))
 	(#.+char-attr-multiple-escape+ (go MULT-ESCAPE))
@@ -956,12 +1090,14 @@
 		;; a FIND-PACKAGE* function analogous to INTERN*
 		;; and friends?
 		(read-buffer-to-string)
-		*keyword-package*))
+		(if seen-multiple-escapes
+		    (read-buffer-to-string)
+		    *keyword-package*)))
       (reset-read-buffer)
       (setq escapes ())
       (setq char (read-char stream nil nil))
       (unless char (reader-eof-error stream "after reading a colon"))
-      (case (char-class char attribute-table)
+      (case (char-class char attribute-array attribute-hash-table)
 	(#.+char-attr-delimiter+
 	 (unread-char char stream)
 	 (%reader-error stream
@@ -976,7 +1112,7 @@
       (setq char (read-char stream nil nil))
       (unless char
 	(reader-eof-error stream "after reading a colon"))
-      (case (char-class char attribute-table)
+      (case (char-class char attribute-array attribute-hash-table)
 	(#.+char-attr-delimiter+
 	 (unread-char char stream)
 	 (%reader-error stream
@@ -1120,7 +1256,7 @@
 				 (the index (* num base))))))))
        (setq number (+ num (* number base-power)))))))
 
-(defun make-float ()
+(defun make-float (stream)
   ;; Assume that the contents of *read-buffer* are a legal float, with nothing
   ;; else after it.
   (read-unwind-read-buffer)
@@ -1154,7 +1290,8 @@
     (cond ((eofp char)
 	   ;; If not, we've read the whole number.
 	   (let ((num (make-float-aux number divisor
-				      *read-default-float-format*)))
+				      *read-default-float-format*
+				      stream)))
 	     (return-from make-float (if negative-fraction (- num) num))))
 	  ((exponent-letterp char)
 	   (setq float-char char)
@@ -1172,63 +1309,28 @@
 		((not dig)
 		 (setq exponent (if negative-exponent (- exponent) exponent)))
 	     (setq exponent (+ (* exponent 10) dig)))
-	   ;; Generate and return the float, depending on float-char:
+	   ;; Generate and return the float, depending on FLOAT-CHAR:
 	   (let* ((float-format (case (char-upcase float-char)
 				  (#\E *read-default-float-format*)
 				  (#\S 'short-float)
 				  (#\F 'single-float)
 				  (#\D 'double-float)
 				  (#\L 'long-float)))
-		  num)
-	     ;; toy@rtp.ericsson.se: We need to watch out if the
-	     ;; exponent is too small or too large. We add enough to
-	     ;; EXPONENT to make it within range and scale NUMBER
-	     ;; appropriately. This should avoid any unnecessary
-	     ;; underflow or overflow problems.
-	     (multiple-value-bind (min-expo max-expo)
-		 ;; FIXME: These #. forms are broken w.r.t.
-		 ;; cross-compilation portability. Maybe expressions
-		 ;; like
-		 ;;   (LOG SB!XC:MOST-POSITIVE-SHORT-FLOAT 10s0)
-		 ;; could be used instead? Or perhaps some sort of
-		 ;; load-time-form magic?
-		 (case float-format
-		   (short-float
-		    (values
-		     #.(log least-positive-normalized-short-float 10s0)
-		     #.(log most-positive-short-float 10s0)))
-		   (single-float
-		    (values
-		     #.(log least-positive-normalized-single-float 10f0)
-		     #.(log most-positive-single-float 10f0)))
-		   (double-float
-		    (values
-		     #.(log least-positive-normalized-double-float 10d0)
-		     #.(log most-positive-double-float 10d0)))
-		   (long-float
-		    (values
-		     #.(log least-positive-normalized-long-float 10L0)
-		     #.(log most-positive-long-float 10L0))))
-	       (let ((correction (cond ((<= exponent min-expo)
-					(ceiling (- min-expo exponent)))
-				       ((>= exponent max-expo)
-					(floor (- max-expo exponent)))
-				       (t
-					0))))
-		 (incf exponent correction)
-		 (setf number (/ number (expt 10 correction)))
-		 (setq num (make-float-aux number divisor float-format))
-		 (setq num (* num (expt 10 exponent)))
-		 (return-from make-float (if negative-fraction
-					     (- num)
-					     num))))))
-	  ;; should never happen
+		  (result (make-float-aux (* (expt 10 exponent) number)
+					  divisor float-format stream)))
+	     (return-from make-float
+	       (if negative-fraction (- result) result))))
 	  (t (bug "bad fallthrough in floating point reader")))))
 
-(defun make-float-aux (number divisor float-format)
-  (coerce (/ number divisor) float-format))
+(defun make-float-aux (number divisor float-format stream)
+  (handler-case
+      (coerce (/ number divisor) float-format)
+    (type-error (c)
+      (error 'reader-impossible-number-error
+	     :error c :stream stream
+	     :format-control "failed to build float"))))
 
-(defun make-ratio ()
+(defun make-ratio (stream)
   ;; Assume *READ-BUFFER* contains a legal ratio. Build the number from
   ;; the string.
   ;;
@@ -1252,13 +1354,18 @@
 	  (dig ()))
 	 ((or (eofp ch) (not (setq dig (digit-char-p ch *read-base*)))))
 	 (setq denominator (+ (* denominator *read-base*) dig)))
-    (let ((num (/ numerator denominator)))
+    (let ((num (handler-case
+		   (/ numerator denominator)
+		 (arithmetic-error (c)
+		   (error 'reader-impossible-number-error
+			  :error c :stream stream
+			  :format-control "failed to build ratio")))))
       (if negative-number (- num) num))))
 
 ;;;; cruft for dispatch macros
 
 (defun make-char-dispatch-table ()
-  (make-array char-code-limit :initial-element #'dispatch-char-error))
+  (make-hash-table))
 
 (defun dispatch-char-error (stream sub-char ignore)
   (declare (ignore ignore))
@@ -1297,9 +1404,7 @@
 	 (dpair (find disp-char (dispatch-tables rt)
 		      :test #'char= :key #'car)))
     (if dpair
-	(setf (elt (the simple-vector (cdr dpair))
-		   (char-code sub-char))
-	      (coerce function 'function))
+	(setf (gethash sub-char (cdr dpair)) (coerce function 'function))
 	(error "~S is not a dispatch char." disp-char))))
 
 (defun get-dispatch-macro-character (disp-char sub-char
@@ -1307,15 +1412,13 @@
   #!+sb-doc
   "Return the macro character function for SUB-CHAR under DISP-CHAR
    or NIL if there is no associated function."
-  (unless (digit-char-p sub-char)
-    (let* ((sub-char (char-upcase sub-char))
-	   (rt (or rt *standard-readtable*))
-	   (dpair (find disp-char (dispatch-tables rt)
-			:test #'char= :key #'car)))
-      (if dpair
-	  (elt (the simple-vector (cdr dpair))
-	       (char-code sub-char))
-	  (error "~S is not a dispatch char." disp-char)))))
+  (let* ((sub-char (char-upcase sub-char))
+         (rt (or rt *standard-readtable*))
+         (dpair (find disp-char (dispatch-tables rt)
+                      :test #'char= :key #'car)))
+    (if dpair
+        (values (gethash sub-char (cdr dpair)))
+        (error "~S is not a dispatch char." disp-char))))
 
 (defun read-dispatch-char (stream char)
   ;; Read some digits.
@@ -1338,8 +1441,7 @@
 		       :test #'char= :key #'car)))
       (if dpair
 	  (funcall (the function
-			(elt (the simple-vector (cdr dpair))
-			     (char-code sub-char)))
+                     (gethash sub-char (cdr dpair) #'dispatch-char-error))
 		   stream sub-char (if numargp numarg nil))
 	  (%reader-error stream "no dispatch table for dispatch char")))))
 
@@ -1350,7 +1452,7 @@
   #!+sb-doc
   "A resource of string streams for Read-From-String.")
 
-(defun read-from-string (string &optional eof-error-p eof-value
+(defun read-from-string (string &optional (eof-error-p t) eof-value
 				&key (start 0) end
 				preserve-whitespace)
   #!+sb-doc
@@ -1358,14 +1460,15 @@
    and the lisp object built by the reader is returned. Macro chars
    will take effect."
   (declare (string string))
+  
   (with-array-data ((string string)
 		    (start start)
-		    (end (or end (length string))))
+		    (end (%check-vector-sequence-bounds string start end)))
     (unless *read-from-string-spares*
-      (push (internal-make-string-input-stream "" 0 0)
-	    *read-from-string-spares*))
+      (push (make-string-input-stream "" 0 0) *read-from-string-spares*))
     (let ((stream (pop *read-from-string-spares*)))
-      (setf (string-input-stream-string stream) string)
+      (setf (string-input-stream-string stream)
+	    (coerce string '(simple-array character (*))))
       (setf (string-input-stream-current stream) start)
       (setf (string-input-stream-end stream) end)
       (unwind-protect
@@ -1383,51 +1486,55 @@
   (default to the beginning and end of the string)  It skips over
   whitespace characters and then tries to parse an integer. The
   radix parameter must be between 2 and 36."
-  (with-array-data ((string string)
-		    (start start)
-		    (end (or end (length string))))
-    (let ((index (do ((i start (1+ i)))
-		     ((= i end)
-		      (if junk-allowed
-			  (return-from parse-integer (values nil end))
-			  (error "no non-whitespace characters in number")))
-		   (declare (fixnum i))
-		   (unless (whitespacep (char string i)) (return i))))
-	  (minusp nil)
-	  (found-digit nil)
-	  (result 0))
-      (declare (fixnum index))
-      (let ((char (char string index)))
-	(cond ((char= char #\-)
-	       (setq minusp t)
-	       (incf index))
-	      ((char= char #\+)
-	       (incf index))))
-      (loop
-	(when (= index end) (return nil))
-	(let* ((char (char string index))
-	       (weight (digit-char-p char radix)))
-	  (cond (weight
-		 (setq result (+ weight (* result radix))
-		       found-digit t))
-		(junk-allowed (return nil))
-		((whitespacep char)
-		 (do ((jndex (1+ index) (1+ jndex)))
-		     ((= jndex end))
-		   (declare (fixnum jndex))
-		   (unless (whitespacep (char string jndex))
-		     (error "junk in string ~S" string)))
-		 (return nil))
-		(t
-		 (error "junk in string ~S" string))))
-	(incf index))
-      (values
-       (if found-digit
-	   (if minusp (- result) result)
-	   (if junk-allowed
-	       nil
-	       (error "no digits in string ~S" string)))
-       index))))
+  (macrolet ((parse-error (format-control)
+	       `(error 'simple-parse-error
+		       :format-control ,format-control
+		       :format-arguments (list string))))
+    (with-array-data ((string string :offset-var offset)
+		      (start start)
+		      (end (%check-vector-sequence-bounds string start end)))
+      (let ((index (do ((i start (1+ i)))
+		       ((= i end)
+			(if junk-allowed
+			    (return-from parse-integer (values nil end))
+			    (parse-error "no non-whitespace characters in string ~S.")))
+		     (declare (fixnum i))
+		     (unless (whitespacep (char string i)) (return i))))
+	    (minusp nil)
+	    (found-digit nil)
+	    (result 0))
+	(declare (fixnum index))
+	(let ((char (char string index)))
+	  (cond ((char= char #\-)
+		 (setq minusp t)
+		 (incf index))
+		((char= char #\+)
+		 (incf index))))
+	(loop
+	 (when (= index end) (return nil))
+	 (let* ((char (char string index))
+		(weight (digit-char-p char radix)))
+	   (cond (weight
+		  (setq result (+ weight (* result radix))
+			found-digit t))
+		 (junk-allowed (return nil))
+		 ((whitespacep char)
+                  (loop
+                   (incf index)
+                   (when (= index end) (return))
+                   (unless (whitespacep (char string index))
+		      (parse-error "junk in string ~S")))
+		  (return nil))
+		 (t
+		  (parse-error "junk in string ~S"))))
+	 (incf index))
+	(values
+	 (if found-digit
+	     (if minusp (- result) result)
+	     (if junk-allowed
+		 nil
+		 (parse-error "no digits in string ~S")))
+	 (- index offset))))))
 
 ;;;; reader initialization code