*** generic/tclCmdMZ.c.orig	Wed May 26 00:34:40 1999
--- generic/tclCmdMZ.c	Thu Jul 15 14:48:52 1999
***************
*** 2047,2052 ****
--- 2047,2053 ----
      enum options {
  	OPT_EXACT,	OPT_GLOB,	OPT_REGEXP,	OPT_LAST
      };
+     int splitObjs, seenComment;
  
      mode = OPT_EXACT;
      for (i = 1; i < objc; i++) {
***************
*** 2080,2085 ****
--- 2081,2087 ----
       * argument, split them out again.
       */
  
+     splitObjs = 0;
      if (objc == 1) {
  	Tcl_Obj **listv;
  
***************
*** 2087,2099 ****
--- 2089,2114 ----
  	    return TCL_ERROR;
  	}
  	objv = listv;
+ 	splitObjs = 1;
      }
  
+     seenComment = 0;
      for (i = 0; i < objc; i += 2) {
  	if (i == objc - 1) {
  	    Tcl_ResetResult(interp);
  	    Tcl_AppendToObj(Tcl_GetObjResult(interp),
  	            "extra switch pattern with no body", -1);
+ 
+ 	    /*
+ 	     * Check if this can be due to a badly placed comment
+ 	     * in the switch block
+ 	     */
+ 
+ 	    if (splitObjs && seenComment) {
+ 		Tcl_AppendToObj(Tcl_GetObjResult(interp),
+ 			"; this can be due to a comment incorrectly placed outside a switch body - see the Tcl and switch man pages", -1);
+ 	    }
+ 
  	    return TCL_ERROR;
  	}
  
***************
*** 2102,2107 ****
--- 2117,2133 ----
  	 */
  
  	pattern = Tcl_GetString(objv[i]);
+ 
+ 	/*
+ 	 * The following is an heuristic to detect the infamous
+ 	 * "comment in switch" error: just check if a pattern
+ 	 * begins with '#'.
+ 	 */
+ 
+ 	if (splitObjs && *pattern == '#') {
+ 	    seenComment = 1;
+ 	}
+ 
  	matched = 0;
  	if ((i == objc - 2) 
  		&& (*pattern == 'd') 
*** generic/tclGet.c.orig	Fri Apr 16 23:01:20 1999
--- generic/tclGet.c	Thu Jul 15 14:05:32 1999
***************
*** 71,76 ****
--- 71,77 ----
          if (interp != (Tcl_Interp *) NULL) {
              Tcl_AppendResult(interp, "expected integer but got \"", string,
                      "\"", (char *) NULL);
+ 	    TclCheckBadOctal(interp, p);
          }
  	return TCL_ERROR;
      }
***************
*** 157,162 ****
--- 158,164 ----
          if (interp != (Tcl_Interp *) NULL) {
              Tcl_AppendResult(interp, "expected integer but got \"", string,
                      "\"", (char *) NULL);
+ 	    TclCheckBadOctal(interp, p);
          }
  	return TCL_ERROR;
      }
*** generic/tclObj.c.orig	Thu May 13 00:47:16 1999
--- generic/tclObj.c	Thu Jul 15 14:08:24 1999
***************
*** 1685,1690 ****
--- 1685,1691 ----
  	    sprintf(buf, "expected integer but got \"%.50s\"", string);
  	    Tcl_ResetResult(interp);
  	    Tcl_AppendToObj(Tcl_GetObjResult(interp), buf, -1);
+ 	    TclCheckBadOctal(interp, p);
  	}
  	return TCL_ERROR;
      }
*** generic/tclExecute.c.orig	Fri Apr 16 23:01:20 1999
--- generic/tclExecute.c	Thu Jul 15 15:14:00 1999
***************
*** 3080,3085 ****
--- 3080,3088 ----
  		(isDouble? "floating-point value" : "non-numeric string"),
  		" as operand of \"", operatorStrings[opCode - INST_LOR],
  		"\"", (char *) NULL);
+ 	if (opndPtr->typePtr != &tclDoubleType) {
+ 	    TclCheckBadOctal(interp, Tcl_GetString(opndPtr));
+ 	}
      }
  }
  
*** generic/tclUtil.c.orig	Wed May 26 00:34:40 1999
--- generic/tclUtil.c	Thu Jul 15 14:56:24 1999
***************
*** 2249,2258 ****
--- 2249,2311 ----
  			       "bad index \"", bytes,
  			       "\": must be integer or end?-integer?",
  			       (char *) NULL);
+ 	TclCheckBadOctal(interp, bytes);
        }
        return TCL_ERROR;
      }
      return TCL_OK;
+ }
+ 
+ /*
+  *----------------------------------------------------------------------
+  *
+  * TclCheckBadOctal --
+  *
+  *	This procedure checks for a bad octal value and appends a
+  *	meaningful error to the interp's result.
+  *
+  * Results:
+  *	1 if the argument was a bad octal, else 0.
+  *
+  * Side effects:
+  *	The interpreter's result is modified.
+  *
+  *----------------------------------------------------------------------
+  */
+ 
+ int
+ TclCheckBadOctal(interp, value)
+     Tcl_Interp *interp;		/* Interpreter to use for error reporting. 
+ 				 * If NULL, then no error message is left
+ 				 * after errors. */
+     char *value;		/* String to check. */
+ {
+     char *p;
+ 
+     /*
+      * A frequent mistake is invalid octal values due to an unwanted
+      * leading zero. Try to generate a meaningful error message.
+      */
+ 
+     p = value;
+     if (*p == '+' || *p == '-') {
+ 	p++;
+     }
+     if (*p == '0') {
+ 	while (isdigit(UCHAR(*p))) {
+ 	    p++;
+ 	}
+ 	if (*p == '\0') {
+ 	    /* Reached end of string */
+ 	    if (interp) {
+ 		Tcl_AppendResult(interp,
+ 		    "; \"", value, "\" uses an incorrect octal representation - see the expr man page",
+ 		    (char *) NULL);
+ 	    }
+ 	    return 1;
+ 	}
+     }
+     return 0;
  }
  
  /*
*** generic/tclInt.h.orig	Wed May 26 00:34:40 1999
--- generic/tclInt.h	Thu Jul 15 14:20:26 1999
***************
*** 1544,1549 ****
--- 1544,1551 ----
  EXTERN void		TclAllocateFreeObjects _ANSI_ARGS_((void));
  EXTERN int		TclArraySet _ANSI_ARGS_((Tcl_Interp *interp,
  			    Tcl_Obj *arrayNameObj, Tcl_Obj *arrayElemObj));
+ EXTERN int		TclCheckBadOctal _ANSI_ARGS_((Tcl_Interp *interp,
+ 			    char *value));
  EXTERN int		TclCleanupChildren _ANSI_ARGS_((Tcl_Interp *interp,
  			    int numPids, Tcl_Pid *pidPtr,
  			    Tcl_Channel errorChan));