[elnygren]

I wonder which is more closer: 3years or "a week or two" to learn enough haskell to start writing things with it.

At least for OCaml/ReasonML it was "less than a week" for me and Haskell is probably not that much harder than another ML.

[iLemming]

No, you cannot realistically learn Haskell in two weeks and jump into industrial Haskell codebase. I mean, it is not impossible - I just never heard such stories. If that was as easy as you think it is - Haskell would be much, much more popular. It is an amazing language. And probably the only point of criticism you can think of is exactly that: it takes quite some dedication and time to grok it.