On: Flow vs. Typescript

[chvid]

I work on / have worked on fairly big projects. Plenty of them have been "a challenge to work with". Always because of the code that had been written (+ other things). Never because of the language.

For me the trick to big projects is strong modularisation and well-defined interfaces which you can do regardless if you have static type checks or not.

[chvid → chvid]

Plus. I think that there is a bit of developer-psychology-101 here.

Most developers would rather go: This project sucks. This shitty language has not got a proper type system. Let's build a compiler/type-checker/use-this-cool-alpha-from-bingo-banana-I-found-last-night.

Rather than: This project sucks. I cannot believe how much bad, disorganised code we have written. Let's sit down and look at our mess to see if we can improve the way we write code, work together and in general develop way we make software.

[plgs → chvid]

I don't see these as mutually exclusive. Introducing a compiler/type-checker can be (depending on your situation) a very concrete way of improving the way code is written.

[chvid → plgs]

They are not. But the pscyhology is that people will much rather talk about introducing a new tool rather than what they have done wrong.

[cgag → chvid]

Yeah, but when you have static typing, you can't avoid well-defined interfaces.

[chvid → cgag]

Let's pick an example:

    function renderMarkdownToHtml(text)

And with static types:

    function renderMarkdownToHtml(text : String) : String

Well-defined interfaces is mostly not about types.

[glibgil → chvid]

When you want

    function render(markdown : Markdown) : Html

then you will see the reason for types (and lots of them)

[chvid → glibgil]

Yep.

And there you have it.

Two different approaches to buidling software.

Which is more productive, which yields higher quality?

I have build plenty of software both ways. And my answer is a confident "it depends". But I will tell you this: A fine-grained type hierarchy over either Markdown or HTML opens up a very big can of worms.

All this reminds me of SOAP vs. HTTP/JSON: I have seen plenty of SOAP webservices seriously stuffed up regardless of/because of strong typing whereas developers seem to do much better with HTTP/JSON because of the simplicity and directness of the approach.

[chii → chvid]

does renderMarkdownToHtml return a string or does it return a DOM element?