X-Git-Url: http://git.hcoop.net/bpt/emacs.git/blobdiff_plain/6d5eb5b0d2e50b0dd153a988cc52492cb77fc333..e5a69fd00a424f59f2ef7be8049b47340ddaa1ca:/src/eval.c

diff --git a/src/eval.c b/src/eval.c
index 079c7ecb6c..4a3f5083b3 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -1,5 +1,5 @@
 /* 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.
 
@@ -124,6 +124,12 @@ Lisp_Object Vsignaling_function;
 
 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);
@@ -780,17 +786,15 @@ The return value is BASE-VARIABLE.  */)
 
 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
@@ -799,6 +803,13 @@ load a file defining variables, with this form or with `defconst' or
 `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)
 {
@@ -873,15 +884,19 @@ usage: (defvar SYMBOL &optional INITVALUE DOCSTRING)  */)
 
 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)
 {
@@ -926,13 +941,14 @@ lisp_indirect_variable (Lisp_Object sym)
 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;
@@ -3756,6 +3772,8 @@ alist of active lexical bindings.  */);
   staticpro (&Vsignaling_function);
   Vsignaling_function = Qnil;
 
+  inhibit_lisp_code = Qnil;
+
   defsubr (&Sor);
   defsubr (&Sand);
   defsubr (&Sif);