Omit buffer_slot_type_mismatch and use generic predicates to enforce

the type of per-buffer values where appropriate.
* src/lisp.h (struct Lisp_Buffer_Objfwd): Rename slottype member to
predicate, which is how it's really used now.  Adjust comment.
* src/buffer.h (buffer_slot_type_mismatch): Remove prototype.
* src/buffer.c (buffer_slot_type_mismatch): Remove.
(DEFVAR_PER_BUFFER, defvar_per_buffer): Rename type argument to
predicate.  Adjust comment.
(syms_of_buffer): Use Qsymbolp for major-mode.  Use Qintegerp for
fill-column, left-margin, tab-width, buffer-saved-size,
left-margin-width, right-margin-width, left-fringe-width,
right-fringe-width, scroll-bar-width and buffer-display-count.
Use Qstringp for default-directory, buffer-file-name,
buffer-file-truename and buffer-auto-save-file-name.  Use Qfloatp for
scroll-up-aggressively and scroll-down-aggressively.  Use Qnumberp for
line-spacing.
* src/data.c (store_symval_forwarding): Adjust to call the predicate.
* lisp/cus-start.el (toplevel): Only allow float values for
scroll-up-aggressively and scroll-down-aggressively.
Allow any number for line-spacing.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/lisp.h b/src/lisp.h
index a0dcc9ab5f3..8db61d3623a 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -1450,7 +1450,8 @@ struct Lisp_Buffer_Objfwd
   {
     enum Lisp_Fwd_Type type;    /* = Lisp_Fwd_Buffer_Obj */
     int offset;
-    Lisp_Object slottype; /* Qnil, Lisp_Int, Lisp_Symbol, or Lisp_String.  */
+    /* One of Qnil, Qintegerp, Qsymbolp, Qstringp, Qfloatp or Qnumberp.  */
+    Lisp_Object predicate;
   };
 
 /* struct Lisp_Buffer_Local_Value is used in a symbol value cell when