X-Git-Url: https://sipb.mit.edu/gitweb.cgi/ikiwiki.git/blobdiff_plain/5017ffd8a512c09d3c34764709791812acfc5515..20eacc2c1f74d0ab617dca36378a35920e313a23:/doc/plugins/write.mdwn

diff --git a/doc/plugins/write.mdwn b/doc/plugins/write.mdwn
index 5be90efdf..abad87568 100644
--- a/doc/plugins/write.mdwn
+++ b/doc/plugins/write.mdwn
@@ -96,9 +96,16 @@ languages to ikiwiki.
 Each time a page is rendered, a [[template|templates]] is filled out.
 This hook allows modifying that template. The function is passed the name
 of the page, and a `HTML::Template` object that is the template that will
-be used to generate the page. It can manipulate that template, the most
-common thing to do is probably to call $template->param() to add a new
-custom parameter to the template.
+be used to generate the page. It can manipulate that template object.
+
+The most common thing to do is probably to call $template->param() to add
+a new custom parameter to the template. Note that in order to be robust,
+it's a good idea to check whether the template has a variable before trying
+to set it, as setting a variable that's not present is an error.
+
+	if ($template->query(name => 'foo')) {
+		$template->param("foo" => "bar");
+	}
 
 ## sanitize