[Emacs-diffs] trunk r116799: Recommend not modifying :set's value arg in defcustom (bug#16755).

[Juanma Barranquero]

------------------------------------------------------------
revno: 116799
revision-id: address@hidden
parent: address@hidden
fixes bug: http://debbugs.gnu.org/16755
committer: Juanma Barranquero <address@hidden>
branch nick: trunk
timestamp: Wed 2014-03-19 00:31:17 +0100
message:
  Recommend not modifying :set's value arg in defcustom (bug#16755).
  
  * doc/lispref/customize.texi (Variable Definitions):
  * lisp/custom.el (defcustom): Recommend avoiding
    destructive modification of the value argument of :set.
modified:
  doc/lispref/ChangeLog          changelog-20091113204419-o5vbwnq5f7feedwu-6155
  doc/lispref/customize.texi     
customize.texi-20091113204419-o5vbwnq5f7feedwu-6170
  lisp/ChangeLog                 changelog-20091113204419-o5vbwnq5f7feedwu-1432
  lisp/custom.el                 custom.el-20091113204419-o5vbwnq5f7feedwu-1093

=== modified file 'doc/lispref/ChangeLog'
--- a/doc/lispref/ChangeLog     2014-03-18 21:14:36 +0000
+++ b/doc/lispref/ChangeLog     2014-03-18 23:31:17 +0000
@@ -1,3 +1,8 @@
+2014-03-18  Juanma Barranquero  <address@hidden>
+
+       * customize.texi (Variable Definitions): Recommend avoiding
+       destructive modification of the value argument of :set (bug#16755).
+
 2014-03-18  Stefan Monnier  <address@hidden>
 
        * modes.texi (Auto-Indentation): Mention electric-indent variables.

=== modified file 'doc/lispref/customize.texi'
--- a/doc/lispref/customize.texi        2014-03-18 01:19:03 +0000
+++ b/doc/lispref/customize.texi        2014-03-18 23:31:17 +0000
@@ -353,8 +353,9 @@
 @var{setfunction} should take two arguments, a symbol (the option
 name) and the new value, and should do whatever is necessary to update
 the value properly for this option (which may not mean simply setting
-the option as a Lisp variable).  The default for @var{setfunction} is
address@hidden
+the option as a Lisp variable); preferably, though, it should not
+modify its value argument destructively.  The default for
address@hidden is @code{set-default}.
 
 If you specify this keyword, the variable's documentation string
 should describe how to do the same job in hand-written Lisp code.

=== modified file 'lisp/ChangeLog'
--- a/lisp/ChangeLog    2014-03-18 20:49:24 +0000
+++ b/lisp/ChangeLog    2014-03-18 23:31:17 +0000
@@ -1,3 +1,8 @@
+2014-03-18  Juanma Barranquero  <address@hidden>
+
+       * custom.el (defcustom): Doc fix: recommend avoiding destructive
+       modification of the value argument of :set (bug#16755).
+
 2014-03-18  Stefan Monnier  <address@hidden>
 
        * simple.el (newline-and-indent): Do autofill (bug#17031).

=== modified file 'lisp/custom.el'
--- a/lisp/custom.el    2014-02-10 01:34:22 +0000
+++ b/lisp/custom.el    2014-03-18 23:31:17 +0000
@@ -232,9 +232,10 @@
        given in the `defcustom' call.  The default is
        `custom-initialize-reset'.
 :set   VALUE should be a function to set the value of the symbol
-        when using the Customize user interface.
-       It takes two arguments, the symbol to set and the value to
-       give it.  The default choice of function is `set-default'.
+       when using the Customize user interface.  It takes two arguments,
+       the symbol to set and the value to give it.  The function should
+       not modify its value argument destructively.  The default choice
+       of function is `set-default'.
 :get   VALUE should be a function to extract the value of symbol.
        The function takes one argument, a symbol, and should return
        the current value for that symbol.  The default choice of function