bug#14254: 24.3; read-number fails to recognize faulty numbers (string-to-number to blame)

[Juri Linkov]

>> `call-interactively' doesn't use `read-number'.  It duplicates code
>> from `read-number' with a similar loop to re-read non-numbers.
>
> Could you try and see if/how the C code could be changed to just call
> the Elisp function?

I tried and see no problems with this patch:

=== modified file 'src/callint.c'
--- src/callint.c       2013-02-27 07:42:43 +0000
+++ src/callint.c       2013-04-25 20:41:12 +0000
@@ -34,6 +34,7 @@ (at your option) any later version.
 static Lisp_Object Qenable_recursive_minibuffers;
 
 static Lisp_Object Qhandle_shift_selection;
+static Lisp_Object Qread_number;
 
 Lisp_Object Qmouse_leave_buffer_hook;
 
@@ -683,29 +684,7 @@ (at your option) any later version.
          if (!NILP (prefix_arg))
            goto have_prefix_arg;
        case 'n':               /* Read number from minibuffer.  */
-         {
-           bool first = 1;
-           do
-             {
-               Lisp_Object str;
-               if (! first)
-                 {
-                   message1 ("Please enter a number.");
-                   sit_for (make_number (1), 0, 0);
-                 }
-               first = 0;
-
-               str = Fread_from_minibuffer (callint_message,
-                                            Qnil, Qnil, Qnil, Qnil, Qnil,
-                                            Qnil);
-               if (! STRINGP (str) || SCHARS (str) == 0)
-                 args[i] = Qnil;
-               else
-                 args[i] = Fread (str);
-             }
-           while (! NUMBERP (args[i]));
-         }
-         visargs[i] = args[i];
+         args[i] = call1 (Qread_number, callint_message);
          break;
 
        case 'P':               /* Prefix arg in raw form.  Does no I/O.  */
@@ -903,6 +882,7 @@ (at your option) any later version.
   DEFSYM (Qminus, "-");
   DEFSYM (Qplus, "+");
   DEFSYM (Qhandle_shift_selection, "handle-shift-selection");
+  DEFSYM (Qread_number, "read-number");
   DEFSYM (Qcall_interactively, "call-interactively");
   DEFSYM (Qcommand_debug_status, "command-debug-status");
   DEFSYM (Qenable_recursive_minibuffers, "enable-recursive-minibuffers");

=== modified file 'lisp/subr.el'
--- lisp/subr.el        2013-04-18 00:12:33 +0000
+++ lisp/subr.el        2013-04-25 20:41:35 +0000
@@ -2200,11 +2200,11 @@ (defun read-passwd (prompt &optional con
               ;; And of course, don't keep the sensitive data around.
               (erase-buffer))))))))
 
-;; This should be used by `call-interactively' for `n' specs.
 (defun read-number (prompt &optional default)
   "Read a numeric value in the minibuffer, prompting with PROMPT.
 DEFAULT specifies a default value to return if the user just types RET.
-The value of DEFAULT is inserted into PROMPT."
+The value of DEFAULT is inserted into PROMPT.
+This function is used by the `interactive' code letter `n'."
   (let ((n nil)
        (default1 (if (consp default) (car default) default)))
     (when default1