Developing Web Applications with Haskell(docs.google.com) |
Developing Web Applications with Haskell(docs.google.com) |
I almost got stuck not reading on because I couldn't figure out how to do some exercises but I'm glad I didn't because hindsight shows me that would have been a mistake.
You can get compile time errors instead of runtime for bunch of things.
I also use purescript[2] with purescript-halogen[3] as does slamdata[4]. There's also a video on Purescript halogen[5] that's very interesting.
Purescript is great because the JavaScript it generates is so readable, that if you really need to you can understand the output and make micro-optimizations.
0: https://github.com/ryantrinkle/reflex
1: https://github.com/ryantrinkle/try-reflex
Do you think that Purescript's row typing (as seen in records and the Eff monad/effect system) is a viable replacement for monad transformer stacks? I "get" MT stacks but I find them heavyweight when what is most often desired is commutative set building of capabilities rather than MT-style stacking.
On the other hand, much of React is a natural play out of Haskell's sweet spot. The challenge will be in making Js-alike APIs which handle the flexibility well while maintaining sufficient typing. React-like rendering, virtualdom, data flow... this will all be incredibly naturao.
http://www.apress.com/9781430262503?gtmf=s
Nice timing. Buying now. Thanks for the tip.
Some effects in PureScript look a lot like the effects provided by certain monad transformers (StateT/ST/Ref, ExceptT/Exception, etc.), but there are differences in terms of how things compose. Take StateT and ExceptT for example: you can compose them in two ways, and get two different monad transformer stacks, with different behaviors (surrounding how state propagates when an exception occurs). There are valid use cases for each, but with the ST and Exception effects, there is only one way to combine them: the way the underlying (Javascript) runtimes chooses for us.
There are things which each one can do which the other cannot. Fortunately, we can mix and match in PureScript since we have the purescript-transformers library. A typical arrangement is to stick Eff on the bottom of a monad transformer stack.
_Edit_: of course, everything you can do with a monad transformer can be done more verbosely with pure functions and the underlying monad, so you _could_ replace monad transformers with Eff in many cases, but in practical terms, it might not be all that useable in some cases.