How can that possibly be not obvious?
It's inconceivable we are having this discussion on HN.
It's not so much about cost but about polluting the Google index with obsolete information. For example, look up a Java API and it's very likely that the first link you will get will point to Java 5. Google is not wrong, that API link is most likely the most linked to, but it's very often not the one you are looking for and certainly not the one that the author of the API wants you to find first.
Probably relatedly, some/much of the docs rely on javascript, so they won't run unless you're running through a server. Instead of forcing everyone who wants or needs to see an older version of bootstrap docs to wrangle this non-working stuff in to a server and configure that, massive amounts of time would saved by simply having versioned docs online.
EDIT: the short answers is not to open the index.html file but any of the other .html files (examples, etc) and you should be able to at least navigate around some.
EDIT2: At least some of the javascript stuff is working without loading from a server - not sure why yet, but it's working. The index page still needs to be fixed.
I'm not sure what you're talking about with the JavaScript. JavaScript runs on the client, not the server. Twitter hosts these docs on Github Pages already... static files, no server-side code.
I know where JS runs. I was conflating embedded javascript references as <script src="http....> style javascript. Typically when I am doing JS, the JS is marked up as being served from a domain - an initial assumption would be that it would be trying to pull the js from a server, but it's not (or not caring, or my stuff is cached).
I still side with the others who want/expect hosted and versioned docs from a project of this size/influence.
Edit: the point being that we can point links at pages from previous commits, branches, and tags Shouldn't this help?
[1] that URL was slightly bastardized but I'm sure someone could very quickly whip this up
The latest version of bootstrap only just got released. I think a majority of users will still find the old docs relevant, even weeks later.
Yes, I realise I can still download the docs. But it's more convenient for some people to have it hosted online.
Yes, sometimes people need to be reminded of basic common sense. I do feel entitled to that.
First, it means you can navigate to it by googling "bootstrap 2.0 documentation". If you are using five JavaScript libraries, it can be annoying to have to find the folder for documentation for each library.
Also, you might not even have the documentation locally. Another developer might have set things up and they might not have checked the documentation into version control.
While it would be great if everyone could just magically upgrade, if you've spent a lot of time wrangling some content management system to the "old" bootstrap, you're more likely better off fixing bugs in that site, than upgrading and hoping nothing breaks.
If it's supposed to be used as a framework, I'd say it's common courtesy to provide the old documentation for at least a short period. It's not that hard, see eg: