Well yeah, and all the other things that I like about it. And as for code indexing, Atom doesn't do much of it at all out of the box. Everything is in plugins

Well yeah, and all the other things that I like about it. And as for code indexing, Atom doesn't do much of it at all out of the box. Everything is in plugins (by design). So it can use the full abilities of TypeScript or Flow if you add those plugins, or it can just use TernJS, or it can offer simple string-matching autocomplete. It does as good of a job as what you plug into it does, as all it really does at the core is display text, and give a plugin interface.