I second this request.
--------------------------------------------------------------------------------
I thought about this with a colleague the other day. Here's a sketch of how it might work, if anyone wants to implement it.

Ingredients:

* A @page_links@ join table (two columns, something like: @source_page@ and @linked_page@)
* An observer on the wiki page model
* A method on the wiki page parser that gives an array of links

On save, the source page would delete all its rows in @page_links@, parse the new page content for links, and update the join table with which pages are now linked.

To display "what links here", all that would be needed is a query to give all @page_links@ rows with a @linked_page@ of the currently viewed page. The pages that link to that page are the @source_page@ values in the result of that query.

*Example:*

@page_links@ has no rows.

I create a page called "foo" with this content:

<code>
This is a page about foo. Related topics: [[bar]], [[baz]].
</code>

@page_links@ then has:

|_.source_page|_.linked_page|
|foo|bar|
|foo|baz|

Then, I create a page named "bar":

<code>
This is a page about bar.
</code>

To find the pages that link to "bar", I query for @page_links@ with a @linked_page@ of "bar". Result:

|_.source_page|_.linked_page|
|foo|bar|

So, "foo" is the only page that links to "bar".
--------------------------------------------------------------------------------
+1

Please see also #16996 [Reciprocal links (or, "Related wiki pages")]
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

relates,New,16996,Reciprocal links (or, "Related wiki pages")