In the Elisp manual, I find nothing about `group' as a type symbol. There is an example, in node Simple Types, that uses `group' when explaining type symbol `alist', but `group' is explained nowhere.
This is the example: (defcustom list-alist '(("foo" 1) ("bar" 2) ("baz" 3)) "Each element is a list of the form (KEY VALUE)." :type '(alist :value-type (group integer))) The only explanation is this, given in passing: The `group' widget is used here instead of `list' only because the formatting is better suited for the purpose. What formatting? How is a reader supposed to understand this? Why does the manual speak of "widget" here, anyway? `group' should be explained as a symbol that you can use when defining a :type value in a `defcustom', just as `alist' and :value-type are explained in that context. `group' is not something specific to `alist', in any case. I find this, for instance, in file `cus-edit.el' (as well as many other uses of `group'). :type '(repeat (group (regexp :tag "Match") (sexp :tag "Type"))) It seems that it is quite common to use `group' in `defcustom' :type specs, but it is not documented. If users are to understand `group' only by reading the widget doc, then there should at least be a cross reference to that doc here. How can Elisp programmers know about using `group' in :type specs if it is not documented? Furthermore, if you do go to the trouble of looking up `group' in the Widget manual, this is all you find (in node `group'): The `group' Widget ------------------ This widget simply group other widgets together. Syntax: TYPE ::= (group [KEYWORD ARGUMENT]... TYPE...) The value is a list, with one member for each TYPE. There are no other occurrences of "group" in the Widget manual. And that node certainly doesn't teach us anything about formatting, or how the formatting is different from using `list' in :type. Please document `group' fully in the context of `defcustom' :type specs, explaining how it can be used and how it differs from using `list'. In GNU Emacs 22.1.50.1 (i386-mingw-nt5.1.2600) of 2007-05-22 on LENNART-69DE564 Windowing system distributor `Microsoft Corp.', version 5.1.2600 configured using `configure --with-gcc (3.4) --cflags -Ic:/g/include' _______________________________________________ emacs-pretest-bug mailing list emacs-pretest-bug@gnu.org http://lists.gnu.org/mailman/listinfo/emacs-pretest-bug