Function: local-variable-p

local-variable-p is a function defined in data.c.

Signature

(local-variable-p VARIABLE &optional BUFFER)

Documentation

Non-nil if VARIABLE has a local binding in buffer BUFFER.

BUFFER defaults to the current buffer.

Also see buffer-local-boundp.

View in manual

Probably introduced at or before Emacs version 19.29.

Source Code

// Defined in /usr/src/emacs/src/data.c
{
  struct buffer *buf = decode_buffer (buffer);
  struct Lisp_Symbol *sym;

  CHECK_SYMBOL (variable);
  sym = XSYMBOL (variable);

 start:
  switch (sym->u.s.redirect)
    {
    case SYMBOL_VARALIAS: sym = SYMBOL_ALIAS (sym); goto start;
    case SYMBOL_PLAINVAL: return Qnil;
    case SYMBOL_LOCALIZED:
      {
	Lisp_Object tmp;
	struct Lisp_Buffer_Local_Value *blv = SYMBOL_BLV (sym);
	XSETBUFFER (tmp, buf);
	XSETSYMBOL (variable, sym); /* Update in case of aliasing.  */

	if (BASE_EQ (blv->where, tmp)) /* The binding is already loaded.  */
	  return blv_found (blv) ? Qt : Qnil;
	else
	  return NILP (assq_no_quit (variable, BVAR (buf, local_var_alist)))
	    ? Qnil
	    : Qt;
      }
    case SYMBOL_FORWARDED:
      {
	lispfwd valcontents = SYMBOL_FWD (sym);
	if (BUFFER_OBJFWDP (valcontents))
	  {
	    int offset = XBUFFER_OBJFWD (valcontents)->offset;
	    int idx = PER_BUFFER_IDX (offset);
	    if (idx == -1 || PER_BUFFER_VALUE_P (buf, idx))
	      return Qt;
	  }
	return Qnil;
      }
    default: emacs_abort ();
    }
}