Thank you for your reply. For code completion, I followed the instructions you gave in the github issue for typescript. They were very clear, and I believe code completion is working well now. (I had previously downloaded the "TypescriptCompletion" package, and I wonder if that was interfering with things. I have disabled it.)
For error checking, I am not able to get it to work. There seems to be something off or missing in my system. I have just downloaded a fresh Sublime Text 3 two days ago, so everything should be new. But I am also seeing issues with other plugins--several of them seem to not be working at all.
Like "NativeScript Snippets"--that one worked smoothly on Atom, but it is not doing anything at all on my Sublime. And I downloaded HTMLLint, and that seems to not be working at all (including after quitting and restarting). Similarly, when I go to "Choose Gutter Theme" for SublimeLinter and click on a gutter theme, it makes no difference. Nothing happens.
Maybe there is something else interfering with them. For trying to get SublimeLinter to work with typescript, I have tried to download tslint, but, weirdly, when I go to "PackageControl: Install Packages", there is no tslint result, and no "SublimeLinter-Contrib-tslint" that shows up.
When I download these packages, I general go through package control: install, see that it is downloaded, and then restart sublime. Is there something else I need to do?
One update: for tslint, I looked in the sublime console, and I got this message: "SublimeLinter: tslint output:
No valid rules have been specified". Googling that error has not come up with anything yet.
And I get this too: "SublimeLinter: WARNING: htmllint deactivated, cannot locate '' "