Core MediaWiki doesn't use lambdas. This seems to be an extension related.

Sounds like it's probably whatever extension handles that <fb:comments> tag.

(Extension's tag hook needs to be updated to take the $parser option by value/object rather than by reference -- remove the '&' from it.)

This seems to be maintained at SourceForce, you might want to report it there.

Seems to be this extension?

http://www.mediawiki.org/wiki/Extension:Facebook

They don't seem to have bug reports enabled on the SourceForge project, so you may need to contact the authors directly.

Closing as INVALID. Unfortunately we cannot help you with reports on code that is not being maintained in the Wikimedia repositories.

Anton: Please report the problem to https://github.com/garbear/facebook-mediawiki/issues . Thanks!

garbearucla wrote:

Hi, I'm the author of the facebook extension. A few years ago, the MediaWiki documentation specified pass-by-reference parameters for some hooks. Slowly, a lot of these are quietly being converted to pass-by-value params (4 or 5 breaking changes in the history of my extension). Would I be wise to convert as many of the remaining reference params as possible to guard against future conversions like this?