From: Mauro Aranda <maurooaranda@gmail.com>
Date: Fri, 4 Sep 2020 12:50:40 +0000 (+0200)
Subject: Document :type-error property for customization types
X-Git-Tag: emacs-28.0.90~6254
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=0f793b5658b0a3610c5b5cad5dd8558d5d11ddfe;p=emacs.git

Document :type-error property for customization types

* doc/lispref/customize.texi (Type Keywords): Document :type-error, so
Lisp programs can display a more correct message when the value of a
user option doesn't match its type (bug#23975).
---

diff --git a/doc/lispref/customize.texi b/doc/lispref/customize.texi
index b9c9130a920..c35444f5817 100644
--- a/doc/lispref/customize.texi
+++ b/doc/lispref/customize.texi
@@ -1197,6 +1197,13 @@ current value is valid for the widget.  Otherwise, it should return
 the widget containing the invalid data, and set that widget's
 @code{:error} property to a string explaining the error.
 
+@item :type-error @var{string}
+@kindex type-error@r{, customization keyword}
+@var{string} should be a string that describes why a value doesn't
+match the type, as determined by the @code{:match} function.  When the
+@code{:match} function returns @code{nil}, the widget's @code{:error}
+property will be set to @var{string}.
+
 @ignore
 @item :indent @var{columns}
 Indent this item by @var{columns} columns.  The indentation is used for