On 4 Apr 2008, at 18:47, Rob McBroom wrote:
[...] the Leopard upgrade "broke" TextMate's attempt to take them over
[...] it looks like Apple has taken the ability to do inappropriate things with file types out of the hands of developers, so you might be out of luck.
TextMate declares that it can handle public.data, there is nothing inappropriate about that, nor is it an attempt to take over all your file types, it’s to tell the system that TextMate _can_ handle all your file types (this information is not only used for double-clicks in Finder, it is also used e.g. when dragging a file on top of an application icon to decide whether or not a drop should be allowed).
The problem is that the file type system in OS X is extension based, and while this system is fully configurable (by the user) for files with extension, finding the application to open for files _without_ an extension is based on a heuristic which got changed in Leopard.