Why do you think it's too slow? I have it integrated with Emacs' flymake and it works pretty well. It takes less than a second to run mypy and display its results (with red underline or whatever else you have configured). From my experience, Visual Studio with F# takes similar time to type-check and show errors.
Well, I am start to writing some Typescript with tslint configured on save, and it takes way more than 1 second for a small toy project.
Even just building this project with Typescript compiler takes more than 1 second. And I don't think it is that bad because at least the process is async.
Interesting. I write TypeScript in PyCharm and I get feedback as soon as I write (PyCharm performs save automatically). I don't know how they implemented it that it's so fast.
Well, PyCharm is already doing a lot of parsing for syntax highlighting and autocompletion and other goodies. They're checker implementation probably just takes the AST PyCharm already has available to it, which saves the round-trip of saving to a file and having an outside checker open and re-parse the file.
Ok, I don't know myself, because I stopped looking for the next editor years ago, so I'd like to ask: do you know how long it takes, on average, for IDEs and editors to highlight a type error?
