Add ability to format output

[bcherny]

Options:

• TypeScript Support prettier/prettier#13
• https://github.com/vvakame/typescript-formatter
• Rules that can fix the problems they find palantir/tslint#561
• https://github.com/nojvek/tslint-fix
• http://clang.llvm.org/docs/ClangFormat.html

[darcyparker]

FYI: I filed a request for option to define quotemark for pretty printer here: microsoft/TypeScript#11320

[alexburner]

Hi, I happen to be wandering the web looking for a good typescript autoformatter. FWIW I've seen another option that could be added to your list, clang-format also supports JS/TS. I haven't fully tested this for myself.

Learned it here microsoft/vscode#9514 (comment)

[bcherny]

@alexburner Added it to the list - thanks! On first impression it looks very powerful. Does it support outputting with no semicolons? I couldn't find an option searching through the docs.

[alexburner]

@bcherny happy to share! I'm afraid I haven't had a chance to dive in yet, was just in the research phase and got pulled into some defect tickets ;) I will be digging further soon, I'll let you know if I run across anything for semicolons.

I can say:

• the angular team appears to use it, and has created a well-maintained npm module: https://github.com/angular/clang-format
• there's a good list of formatting options here, but no mention of semicolons: http://clang.llvm.org/docs/ClangFormatStyleOptions.html