add influence info to match_*

Also update docs, test suite.

1 files changed, 7 insertions, 0 deletions

diff --git a/doc/plugins/write.mdwn b/doc/plugins/write.mdwn
index 8e8c3311e..6b47033e5 100644
--- a/doc/plugins/write.mdwn
+++ b/doc/plugins/write.mdwn
@@ -982,6 +982,13 @@ an IkiWiki::FailReason object if the match fails. If the match cannot be
 attempted at all, for any page, it can instead return an
 IkiWiki::ErrorReason object explaining why.
 
+When constructing these objects, you should also include a list of any
+pages whose contents or other metadata influenced the result of the match.
+For example, "backlink(foo)" is influenced by the contents of page foo;
+"link(foo)" and "title(bar)" are influenced by the contents of any
+page they match; "created_before(foo)" is influenced by the metadata of
+foo; while "glob(*)" is not influenced by the contents of any page.
+
 ### Setup plugins
 
 The ikiwiki setup file is loaded using a pluggable mechanism. If you look