improve wording to not encourage explicitly passing undef

diff --git a/doc/plugins/write.mdwn b/doc/plugins/write.mdwn
index fe7cf0183bc4232750fe71a2cde3fb9d9a601bb8..71ff1fd29e42e9333fe25674191a8fc32391edfb 100644 (file)
--- a/doc/plugins/write.mdwn
+++ b/doc/plugins/write.mdwn
@@ -960,8 +960,8 @@ will yield something like `foo/feed.rss`.
 This adds a link to `%links`, ensuring that duplicate links are not
 added. Pass it the page that contains the link, and the link text.
 
-An optional third parameter sets the link type (`undef` produces an ordinary
-[[ikiwiki/WikiLink]]).
+An optional third parameter sets the link type. If not specified,
+it is an ordinary [[ikiwiki/WikiLink]].
 
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