An interesting debate sparked on the forums of Hacker News: what are the benefits of coding in Haskell and why should we use it?
Here are the main points:
* Haskell is (very) strongly and statically typed and Python isn't. Haskell's type system can prove the correctness of many functions at compile time. In contrast, Python usually waits until runtime to throw exceptions, even for something obvious like a syntax error.
* Because the types are known, there's an incredibly powerful testing framework called QuickCheck that is capable of e.g. generating tens of thousands of valid inputs and seeing if it can automatically disprove your assertions about your code. Python's typing is insufficient for this.
* Qualitatively, writing Python feels like writing instructions for computing something, and writing Haskell feels like simply describing what something is, and the system works out how to compute it for you. It often feels compelling and magical.