/* Evaluator for GNU Emacs Lisp interpreter.
- Copyright (C) 1985-1987, 1993-1995, 1999-2011 Free Software Foundation, Inc.
+ Copyright (C) 1985-1987, 1993-1995, 1999-2012 Free Software Foundation, Inc.
This file is part of GNU Emacs.
int handling_signal;
+/* If non-nil, Lisp code must not be run since some part of Emacs is
+ in an inconsistent state. Currently, x-create-frame uses this to
+ avoid triggering window-configuration-change-hook while the new
+ frame is half-initialized. */
+Lisp_Object inhibit_lisp_code;
+
static Lisp_Object funcall_lambda (Lisp_Object, ptrdiff_t, Lisp_Object *);
static void unwind_to_catch (struct catchtag *, Lisp_Object) NO_RETURN;
static int interactive_p (int);
args_left = Fcdr (Fcdr (args_left));
}
- while (!NILP(args_left));
+ while (!NILP (args_left));
UNGCPRO;
return val;
DEFUN ("quote", Fquote, Squote, 1, UNEVALLED, 0,
doc: /* Return the argument, without evaluating it. `(quote x)' yields `x'.
+Warning: `quote' does not construct its return value, but just returns
+the value that was pre-constructed by the Lisp reader (see info node
+`(elisp)Printed Representation').
+This means that '(a . b) is not identical to (cons 'a 'b): the former
+does not cons. Quoting should be reserved for constants that will
+never be modified by side-effects, unless you like self-modifying code.
+See the common pitfall in info node `(elisp)Rearrangement' for an example
+of unexpected results when a quoted object is modified.
usage: (quote ARG) */)
(Lisp_Object args)
{
DEFUN ("defvar", Fdefvar, Sdefvar, 1, UNEVALLED, 0,
doc: /* Define SYMBOL as a variable, and return SYMBOL.
-You are not required to define a variable in order to use it,
-but the definition can supply documentation and an initial value
-in a way that tags can recognize.
-
-INITVALUE is evaluated, and used to set SYMBOL, only if SYMBOL's value is void.
-If SYMBOL is buffer-local, its default value is what is set;
- buffer-local values are not affected.
-INITVALUE and DOCSTRING are optional.
-If DOCSTRING starts with *, this variable is identified as a user option.
- This means that M-x set-variable recognizes it.
- See also `user-variable-p'.
+You are not required to define a variable in order to use it, but
+defining it lets you supply an initial value and documentation, which
+can be referred to by the Emacs help facilities and other programming
+tools. The `defvar' form also declares the variable as \"special\",
+so that it is always dynamically bound even if `lexical-binding' is t.
+
+The optional argument INITVALUE is evaluated, and used to set SYMBOL,
+only if SYMBOL's value is void. If SYMBOL is buffer-local, its
+default value is what is set; buffer-local values are not affected.
If INITVALUE is missing, SYMBOL's value is not set.
If SYMBOL has a local binding, then this form affects the local
`defcustom', you should always load that file _outside_ any bindings
for these variables. \(`defconst' and `defcustom' behave similarly in
this respect.)
+
+The optional argument DOCSTRING is a documentation string for the
+variable.
+
+To define a user option, use `defcustom' instead of `defvar'.
+The function `user-variable-p' also identifies a variable as a user
+option if its DOCSTRING starts with *, but this behavior is obsolete.
usage: (defvar SYMBOL &optional INITVALUE DOCSTRING) */)
(Lisp_Object args)
{
DEFUN ("defconst", Fdefconst, Sdefconst, 2, UNEVALLED, 0,
doc: /* Define SYMBOL as a constant variable.
-The intent is that neither programs nor users should ever change this value.
-Always sets the value of SYMBOL to the result of evalling INITVALUE.
-If SYMBOL is buffer-local, its default value is what is set;
- buffer-local values are not affected.
-DOCSTRING is optional.
-
-If SYMBOL has a local binding, then this form sets the local binding's
-value. However, you should normally not make local bindings for
-variables defined with this form.
+This declares that neither programs nor users should ever change the
+value. This constancy is not actually enforced by Emacs Lisp, but
+SYMBOL is marked as a special variable so that it is never lexically
+bound.
+
+The `defconst' form always sets the value of SYMBOL to the result of
+evalling INITVALUE. If SYMBOL is buffer-local, its default value is
+what is set; buffer-local values are not affected. If SYMBOL has a
+local binding, then this form sets the local binding's value.
+However, you should normally not make local bindings for variables
+defined with this form.
+
+The optional DOCSTRING specifies the variable's documentation string.
usage: (defconst SYMBOL INITVALUE [DOCSTRING]) */)
(Lisp_Object args)
{
DEFUN ("user-variable-p", Fuser_variable_p, Suser_variable_p, 1, 1, 0,
doc: /* Return t if VARIABLE is intended to be set and modified by users.
\(The alternative is a variable used internally in a Lisp program.)
-A variable is a user variable if
-\(1) the first character of its documentation is `*', or
-\(2) it is customizable (its property list contains a non-nil value
- of `standard-value' or `custom-autoload'), or
-\(3) it is an alias for another user variable.
-Return nil if VARIABLE is an alias and there is a loop in the
-chain of symbols. */)
+
+This function returns t if (i) the first character of its
+documentation is `*', or (ii) it is customizable (its property list
+contains a non-nil value of `standard-value' or `custom-autoload'), or
+\(iii) it is an alias for a user variable.
+
+But condition (i) is considered obsolete, so for most purposes this is
+equivalent to `custom-variable-p'. */)
(Lisp_Object variable)
{
Lisp_Object documentation;
static int maybe_call_debugger (Lisp_Object conditions, Lisp_Object sig,
Lisp_Object data);
+void
+process_quit_flag (void)
+{
+ Lisp_Object flag = Vquit_flag;
+ Vquit_flag = Qnil;
+ if (EQ (flag, Qkill_emacs))
+ Fkill_emacs (Qnil);
+ if (EQ (Vthrow_on_input, flag))
+ Fthrow (Vthrow_on_input, Qt);
+ Fsignal (Qquit, Qnil);
+}
+
DEFUN ("signal", Fsignal, Ssignal, 2, 2, 0,
doc: /* Signal an error. Args are ERROR-SYMBOL and associated DATA.
This function does not return.
A value of `(t)' indicates an empty environment, otherwise it is an
alist of active lexical bindings. */);
Vinternal_interpreter_environment = Qnil;
- /* Don't export this variable to Elisp, so noone can mess with it
+ /* Don't export this variable to Elisp, so no one can mess with it
(Just imagine if someone makes it buffer-local). */
Funintern (Qinternal_interpreter_environment, Qnil);
staticpro (&Vsignaling_function);
Vsignaling_function = Qnil;
+ inhibit_lisp_code = Qnil;
+
defsubr (&Sor);
defsubr (&Sand);
defsubr (&Sif);
HCoop / bpt / emacs.git / blobdiff