(evaporate_overlays): Overlay is in car, not cdr.

[bpt/emacs.git] / src / eval.c

diff --git a/src/eval.c b/src/eval.c
index ea608d3..f5631c3 100644 (file)
--- a/src/eval.c
+++ b/src/eval.c
@@ -1,5 +1,5 @@
 /* Evaluator for GNU Emacs Lisp interpreter.
-   Copyright (C) 1985, 1986, 1987, 1993 Free Software Foundation, Inc.
+   Copyright (C) 1985, 1986, 1987, 1993, 1994 Free Software Foundation, Inc.
 
 This file is part of GNU Emacs.
 
@@ -149,9 +149,11 @@ extern Lisp_Object ml_apply (); /* Apply a mocklisp function to unevaluated argu
 init_eval_once ()
 {
   specpdl_size = 50;
-  specpdl = (struct specbinding *) malloc (specpdl_size * sizeof (struct specbinding));
+  specpdl = (struct specbinding *) xmalloc (specpdl_size * sizeof (struct specbinding));
   max_specpdl_size = 600;
   max_lisp_eval_depth = 200;
+
+  Vrun_hooks = Qnil;
 }
 
 init_eval ()
@@ -163,7 +165,8 @@ init_eval ()
   Vquit_flag = Qnil;
   debug_on_next_call = 0;
   lisp_eval_depth = 0;
-  when_entered_debugger = 0;
+  /* This is less than the initial value of num_nonmacro_input_chars.  */
+  when_entered_debugger = -1;
 }
 
 Lisp_Object
@@ -377,7 +380,7 @@ whose values are discarded.")
 }
 
 DEFUN ("prog2", Fprog2, Sprog2, 2, UNEVALLED, 0,
-  "(prog1 X Y BODY...): eval X, Y and BODY sequentially; value from Y.\n\
+  "(prog2 X Y BODY...): eval X, Y and BODY sequentially; value from Y.\n\
 The value of Y is saved during the evaluation of the remaining args,\n\
 whose values are discarded.")
   (args)
@@ -390,7 +393,7 @@ whose values are discarded.")
 
   val = Qnil;
 
-  if (NILP(args))
+  if (NILP (args))
     return Qnil;
 
   args_left = args;
@@ -405,7 +408,7 @@ whose values are discarded.")
        Feval (Fcar (args_left));
       args_left = Fcdr (args_left);
     }
-  while (!NILP(args_left));
+  while (!NILP (args_left));
 
   UNGCPRO;
   return val;
@@ -413,8 +416,12 @@ whose values are discarded.")
 
 DEFUN ("setq", Fsetq, Ssetq, 0, UNEVALLED, 0,
   "(setq SYM VAL SYM VAL ...): set each SYM to the value of its VAL.\n\
-The SYMs are not evaluated.  Thus (setq x y) sets x to the value of y.\n\
-Each SYM is set before the next VAL is computed.")
+The symbols SYM are variables; they are literal (not evaluated).\n\
+The values VAL are expressions; they are evaluated.\n\
+Thus, (setq x (1+ y)) sets `x' to the value of `(1+ y)'.\n\
+The second VAL is not computed until after the first SYM is set, and so on;\n\
+each VAL can use the new value of variables set earlier in the `setq'.\n\
+The return value of the `setq' form is the value of the last VAL.")
   (args)
      Lisp_Object args;
 {
@@ -1194,7 +1201,7 @@ See also the function `condition-case'.")
          struct handler *h = handlerlist;
 
          handlerlist = allhandlers;
-         if (data == memory_signal_data)
+         if (EQ (data, memory_signal_data))
            unwind_data = memory_signal_data;
          else
            unwind_data = Fcons (error_symbol, data);
@@ -1326,7 +1333,11 @@ error (m, a1, a2, a3)
       size *= 2;
       if (allocated)
        buffer = (char *) xrealloc (buffer, size);
-      buffer = (char *) xmalloc (size);
+      else
+       {
+         buffer = (char *) xmalloc (size);
+         allocated = 1;
+       }
     }
 
   string = build_string (buf);
@@ -2262,8 +2273,7 @@ specbind (symbol, value)
     grow_specpdl ();
   specpdl_ptr->symbol = symbol;
   specpdl_ptr->func = 0;
-  ovalue = XSYMBOL (symbol)->value;
-  specpdl_ptr->old_value = EQ (ovalue, Qunbound) ? Qunbound : Fsymbol_value (symbol);
+  specpdl_ptr->old_value = ovalue = find_symbol_value (symbol);
   specpdl_ptr++;
   if (XTYPE (ovalue) == Lisp_Buffer_Objfwd)
     store_symval_forwarding (symbol, ovalue, value);
@@ -2400,6 +2410,7 @@ Output stream used is value of `standard-output'.")
       if (backlist->nargs == UNEVALLED)
        {
          Fprin1 (Fcons (*backlist->function, *backlist->args), Qnil);
+         write_string ("\n", -1);
        }
       else
        {
@@ -2424,8 +2435,8 @@ Output stream used is value of `standard-output'.")
                  Fprin1 (backlist->args[i], Qnil);
                }
            }
+         write_string (")\n", -1);
        }
-      write_string (")\n", -1);
       backlist = backlist->next;
     }
 
@@ -2454,7 +2465,7 @@ If N is more than the number of frames, the value is nil.")
   CHECK_NATNUM (nframes, 0);
 
   /* Find the frame requested.  */
-  for (i = 0; i < XFASTINT (nframes); i++)
+  for (i = 0; backlist && i < XFASTINT (nframes); i++)
     backlist = backlist->next;
 
   if (!backlist)
@@ -2486,7 +2497,7 @@ if that proves inconveniently small.");
 
   DEFVAR_LISP ("quit-flag", &Vquit_flag,
     "Non-nil causes `eval' to abort, unless `inhibit-quit' is non-nil.\n\
-Typing C-G sets `quit-flag' non-nil, regardless of `inhibit-quit'.");
+Typing C-g sets `quit-flag' non-nil, regardless of `inhibit-quit'.");
   Vquit_flag = Qnil;
 
   DEFVAR_LISP ("inhibit-quit", &Vinhibit_quit,
@@ -2545,7 +2556,7 @@ See also variable `debug-on-quit'.");
   Vdebug_on_error = Qnil;
 
   DEFVAR_BOOL ("debug-on-quit", &debug_on_quit,
-    "*Non-nil means enter debugger if quit is signaled (C-G, for example).\n\
+    "*Non-nil means enter debugger if quit is signaled (C-g, for example).\n\
 Does not apply if quit is handled by a `condition-case'.");
   debug_on_quit = 0;
 
@@ -2570,7 +2581,6 @@ If due to `eval' entry, one arg, t.");
   DEFVAR_LISP ("run-hooks", &Vrun_hooks,
     "Set to the function `run-hooks', if that function has been defined.\n\
 Otherwise, nil (in a bare Emacs without preloaded Lisp code).");
-  Vrun_hooks = Qnil;
 
   staticpro (&Vautoload_queue);
   Vautoload_queue = Qnil;