(read1): New argument for returning out-of-band data, obviating the need for

Lisp_Internal datatype.
(read0, read1, read_list): Use that new calling sequence.

1 files changed, 37 insertions, 40 deletions

diff --git a/src/lread.c b/src/lread.c
index dce5912d03d..23885cc8ad3 100644
--- a/src/lread.c
+++ b/src/lread.c
@@ -929,8 +929,8 @@ START and END optionally delimit a substring of STRING from which to read;\n\
   return Fcons (tem, make_number (read_from_string_index));
 }
 
-/* Use this for recursive reads, in contexts where internal tokens are not allowed. */
-
+/* Use this for recursive reads, in contexts where internal tokens
+   are not allowed. */
 static Lisp_Object
 read0 (readcharfun)
      Lisp_Object readcharfun;
@@ -938,12 +938,9 @@ read0 (readcharfun)
   register Lisp_Object val;
   char c;
 
-  val = read1 (readcharfun);
-  if (INTERNALP (val))
-    {
-      c = XINT (val);
-      return Fsignal (Qinvalid_read_syntax, Fcons (make_string (&c, 1), Qnil));
-    }
+  val = read1 (readcharfun, &c);
+  if (c)
+    Fsignal (Qinvalid_read_syntax, Fcons (make_string (&c, 1), Qnil));
 
   return val;
 }
@@ -1106,11 +1103,16 @@ read_escape (readcharfun)
     }
 }
 
+/* If the next token is ')' or ']' or '.', we store that character
+   in *PCH and the return value is not interesting.  Else, we store
+   zero in *PCH and we read and return one lisp object.  */
 static Lisp_Object
-read1 (readcharfun)
+read1 (readcharfun, pch)
      register Lisp_Object readcharfun;
+     char *pch;
 {
   register int c;
+  *pch = 0;
 
  retry:
 
@@ -1128,9 +1130,8 @@ read1 (readcharfun)
     case ')':
     case ']':
       {
-        register Lisp_Object val;
-        XSETINTERNAL (val, c);
-        return val;
+        *pch = c;
+        return Qnil;
       }
 
     case '#':
@@ -1149,10 +1150,11 @@ read1 (readcharfun)
         {
           Lisp_Object tmp;
           struct gcpro gcpro1;
+          char ch;
 
           /* Read the string itself.  */
-          tmp = read1 (readcharfun);
-          if (!STRINGP (tmp))
+          tmp = read1 (readcharfun, &ch);
+          if (ch != 0 || !STRINGP (tmp))
             Fsignal (Qinvalid_read_syntax, Fcons (make_string ("#", 1), Qnil));
           GCPRO1 (tmp);
           /* Read the intervals and their properties.  */
@@ -1160,22 +1162,17 @@ read1 (readcharfun)
             {
               Lisp_Object beg, end, plist;
 
-              beg = read1 (readcharfun);
-              if (INTERNALP (beg))
-                {
-                  if (XINT (beg) == ')')
-                    break;
-                  Fsignal (Qinvalid_read_syntax, Fcons (make_string ("invalid string property list", 28), Qnil));
-                }
-              end = read1 (readcharfun);
-              if (INTERNALP (end))
-                Fsignal (Qinvalid_read_syntax,
-                         Fcons (make_string ("invalid string property list", 28), Qnil));
-                
-              plist = read1 (readcharfun);
-              if (INTERNALP (plist))
+              beg = read1 (readcharfun, &ch);
+              if (ch == ')')
+                break;
+              if (ch == 0)
+                end = read1 (readcharfun, &ch);
+              if (ch == 0)
+                plist = read1 (readcharfun, &ch);
+              if (ch)
                 Fsignal (Qinvalid_read_syntax,
-                         Fcons (make_string ("invalid string property list", 28), Qnil));
+                         Fcons (build_string ("invalid string property list"),
+                                Qnil));
               Fset_text_properties (beg, end, plist, tmp);
             }
           UNGCPRO;
@@ -1276,9 +1273,8 @@ read1 (readcharfun)
         if (! isdigit (next_char))
 #endif
           {
-            register Lisp_Object val;
-            XSETINTERNAL (val, c);
-            return val;
+            *pch = c;
+            return Qnil;
           }
 
         /* Otherwise, we fall through!  Note that the atom-reading loop
@@ -1477,29 +1473,30 @@ read_list (flag, readcharfun)
 
   while (1)
     {
+      char ch;
       GCPRO2 (val, tail);
-      elt = read1 (readcharfun);
+      elt = read1 (readcharfun, &ch);
       UNGCPRO;
-      if (INTERNALP (elt))
+      if (ch)
         {
           if (flag > 0)
             {
-              if (XINT (elt) == ']')
+              if (ch == ']')
                 return val;
-              return Fsignal (Qinvalid_read_syntax, Fcons (make_string (") or . in a vector", 18), Qnil));
+              Fsignal (Qinvalid_read_syntax, Fcons (make_string (") or . in a vector", 18), Qnil));
             }
-          if (XINT (elt) == ')')
+          if (ch == ')')
             return val;
-          if (XINT (elt) == '.')
+          if (ch == '.')
             {
               GCPRO2 (val, tail);
               if (!NILP (tail))
                 XCONS (tail)->cdr = read0 (readcharfun);
               else
                 val = read0 (readcharfun);
-              elt = read1 (readcharfun);
+              read1 (readcharfun, &ch);
               UNGCPRO;
-              if (INTERNALP (elt) && XINT (elt) == ')')
+              if (ch == ')')
                 return val;
               return Fsignal (Qinvalid_read_syntax, Fcons (make_string (". in wrong context", 18), Qnil));
             }