TwinPages are a special case of InterWiki links that appear as OutOfLineLinks on a given page. The links point to a page with a similar name (possibly unified through WikiNameCanonicalization) on another wikis. In this way, they act as a sort of AccidentalLinking across wikis. Wikis that are linked in this way are called Wiki:SisterSites in the OriginalWiki?.
The original implementation is on WikiWiki, as dreamt by StevenBlack and WardCunningham. They appear as logos at the bottom of a page. See Wiki:RecentChanges for the full list. See Wiki:TwinPages for a link back to here.
As long as only a handful of wikis are coupled by TwinPages, this is not much of an imposition. Instead of logo at the bottom, one could emulate Twinpages by an manually editable bottom line:
TwinPages: <list of foreign wikis that have a corresponding twinpage.>
Only entries in the InterMap may be added. A click on a foreign wiki's name takes you on the twinpage of the respective forum. This is perhaps more efficient than writing
Wiki1:TwinPages Wiki2:TwinPages Wiki3:TwinPages ..., as you avoid duplicating the page names. Another suggestion for implementing the TwinPages feature is AddTwinPage.
On AllPages, there is also a list of foreign wikis' page indices which you can use to automatically match twin pages. If you have the foreign AllPages listings, you may want to do some WikiNameCanonicalization to find matches between similarly spelt titles. It's now possible to use MetaWiki to give you all the twin pages for your server in one shot.
One case to consider whenever merging two naming systems is "namespace conflicts". Each wiki exists in its own namespace, so a discussion of, say, LinkPattern differs on each site depending on the local context. By not duplicating names, one can get into namespace conflicts. Fundamentally, I think this is because more naming systems are non-context dependent. That is, when I say, "stream," the system will automatically find a reference that matches the name, "stream." However, it's not really clear whether I'm a geography talking about watersheds or I'm a programmer talking about fundamental data structures. In this way, the InterWiki prefix namespaces the two concepts, by allowing one wiki to be a space about cartography and the other to be one about Lisp programming whilst using the same names.
I think, initial restriction to CamelCase will get the 'ball' rolling. Another option would be to use a MediatorWikiForum?, that allows WikiNameMapping? to abitrary WikiNames. I'm experimenting a bit (as a user) on Wiki:SwikiFarm, which allows any strings sss (that can be enclosed like that *sss>html-address*) as WikiNames. This way you can accomodate any WikiName in the target wiki. -- FridemarPache
WikiTunneling. A special or extreme version of the namespace conflict occurs when the two wikis are written in different languages. In my Swedish wiki [susning.nu] I call this translation links. In WikiPedia, a similar approach is called interlanguage linking. The idea is to give the translation as a link. In my wiki I just write the translation (svenska: översättning) in a plain parenthesis (see e.g. http://susning.nu/Jorden), and have the WikiToHTML? sub do the link to some interesting sources in the other language. In WikiPedia, the syntax is a little more like a link, the links only lead to the other WikiPedia projects, and the link is made with a ? or underlinked depending on the existence of the other page. --LarsAronsson
One interesting side effect of TwinPages is the effect that certain page titles cannot be removed from the site because they are available on SisterSites. On WikiWiki, many people have asked why a page they have deleted still remains active, as if it were still on WikiWiki. The answer is apparent once they notice the SisterSites' logos. I've noticed that with some sister sites of WikiWiki, TwinPages have encouraged the importation of issues local to a sister site to WikiWiki that are very off-topic to WikiWiki. Sometimes flame wars move over. Sometimes marketing spam. Regardless of the severity, I think that this potential encouragement of discussions spilling over from a foreign wiki should be questioned, as the local community loses control over its own PageDatabase (e.g. AccidentalLinking, AllPages). I think it would be better if the list of sister sites was controlled by the community, so they can maintain a CommunityExpectation to keep the list small and valuable. Consider the bloat of the local InterMapTxt that occured once it became public. -- SunirShah
Community maintained TwinPages sounds like a great idea. -- BayleShanks
"Community maintained Twin Pages" -- think about what this means. It just means that somebody adds alink to the other page on another wiki. That's it. No magic. Just a link -- or an InterMap link. -- AlexSchroeder
Well, it's a convenient simplification to use the InterMap prefix with empty pagename. E.g. Wiki: would lead to Wiki:TwinPages, if it exists on the target Wiki, otherwise the resp. creation edit page could be shown. Wiki:NonExistent -- FridemarPache
On second thought, I agree with Alex here. It is just a link. However, sometimes to do it that way you would have to create a shallow page; a page containing only the link to the target community (as I did on SisterSites). I see no problem with this (obviously). TwinPages also has the additional effect of subtly encouraging someone to go to the twin page, rather than starting a page by the same name on this wiki. However, this effect isn't very strong and could be done better by having a page containing only the link and the sentence "conversation on ___ is redirected to Wiki:____". This has the additional benefit of making a space for people to disagree with the redirection. -- BayleShanks
How about, in addition, a user-settable option to see all TwinPages (EmpowerIndividuals? what is our canonical name for this force here?)? These would be separate features as the underlying mechanism would likely be different.
I don't worry so much about spillover of unwanted conversation (I feel that wiki communities can effectively limit topical range if they want to strongly enough), but I am worried more about the WikiMass effect. There are a few pages that I've created or even partially duplicated here although they exist on WikiWiki because I feel MeatballWiki is a better forum for them. I assert that this is a good practise. -- BayleShanks
See ReworkingProblems. -- AlexSchroeder
If you are using the same language on three sites and want to interlink them, TwinPages is a good technical solution. However, some pages will be trivial (eg. WhyWikiWorks or TextFormattingRules are often replicated on all wikis as an introduction to newbies), and thus while TwinPages is doable, it is not important. Unless you want to interconnect communities -- to let people know that similar topics are also discussed elsewhere. For this sense of "neighbourhood", TwinPages might work.
Automatic bidirectional links based on referrer seems complicated to implement, and it would make "linking" an unconscious act of all visitors. I don't know whether that is intended. Personally, I think it makes more sense to provide explicit InterWiki links to solve this problem. -- AlexSchroeder.
This page needs reworking. (CategoryToDo)
You can put patches for UseModWiki on UseMod:WikiPatches. As for MeatballWiki, that's up to Meatball, but we are finally switching to OddMuse which has TwinPages implemented. The Search MetaWiki link at the bottom fulfils a similar function. -- SunirShah