My problem is somewhat strange. I have started developing a web page with Aptana Studio build 2.0.5.1278522500. Everything went fine up to the moment when I wanted to start writing JavaScript in a separate .js file - there's no code assist for it. In the preferences it's enabled, and - that's the strange part - it works perfectly well in the .html files (when typing code in the script tag). The only thing that could remotely tell there's something wrong is the fact, that when I type, say, "document" and hit the '.' key, the cursor disappears for a split of a second.
Did anyone have the same problem? Is there any solution to that? I'd like code assist for JS very much, without it Aptana somewhat loses it's appeal.
I found an answer to my question, I'll post because maybe it'll help someone. To get the code assist working I just changed file the default editor for .js files from JavaScript editor to Aptana JS editor (Preferences->General->Editors->File Associations, then selected *.js in the top list and Aptana JS Editor in the bottom list, then clicked the "Default" button). Now it works like a charm.