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Show HN: Haquery – jQuery for Haskell

47 points by friendly_chap 13y ago

friendly_chap 13y ago
Hi, author here. Maybe "jQuery for Haskell" is not too descriptive: it is a pure Haskell html dom manipulation tool, mainly useful for templating and/or scraping. It uses the same selectors and API as jQuery, the only deviations are due to immutability (eg. if you modify a selection, the original graph will not be updated of course, so you have to use "alter" or something similar). Edit: Feel free to send a pull request or suggest any changes. The time I poured into the library was mainly focused on getting even the most complex nested selectors to work, because I felt that is the lion's share of the work.
- tych0 13y ago
  Cool! I have a similar project, based on lift's CssSel's (which are sort of based on the jquery syntax): https://github.com/tych0/hquery https://github.com/tych0/hquery I've been playing around with making a DSL vs. using string based selectors, and I've had little success coming up with something sensible. Have you thought about this at all?
  - friendly_chap 13y ago
    I will check your repo too. If you have problems due to similar naming let me know and I will change it. Regarding the selector DSLs, I also went with the string solution, however I translate all selectors to a recursive ADT which could be used directly. Maybe we should unite our powers ;)
    - tych0 13y ago
      Nah, no issues with naming, mine was just a pet project to pick up a bit of haskell. R.E. uniting forces, yeah! I looked through your code a bit, and it looks like we have the same underlying idea (yours seems a bit less convoluted than mine, though :-). I'm not really actively using hquery for anything more than a static site generator I wrote with it, but I wouldn't mind spending a few more hours/week on haskell code.
      - friendly_chap 13y ago
        Seems like we are on the same page, I also test drived this library with a static site generator =). I was really surprised that there are no more templating languages for Haskell given the availability of the mighty parsec. I am following you on github, stay in touch.
alipang 13y ago
Looks cool. I feel like you should try and integrate with existing Haskell concepts. Maybe you'd have to make small changes in the design decisions compared to jQuery, but honestly, using the typical Haskell abstractions things just seem to be "right" somehow. Queries could easily be modelled with the list monad. Add the stateT transformer for effects. Add lenses for niceness. (Lenses could really beautify the internal implementation as well me thinks). I'd love to hear about some of your design choices making this.
- friendly_chap 13y ago
  Thank you! I definitely agree with you regarding the idiomatic solutions. However, the only defense I can come up with (not that I really want to excuse myself) is this is part of an effort (Hakit) to make Haskell web development accessible to HS beginners. I was a beginner myself when I started Hakit, a web toolkit, and I was overwhelmed by the seemingly complex Haskell APIs. So I tried to build a complete toolkit while forcing the users learning as few Haskell concepts as possible, without writing exceedingly ugly code. I will surely try to make this more appealing to Haskell ninjas too though.
  - jhartikainen 13y ago
    Interesting, as a web dev I agree that getting into Haskell can be a bit tricky due to exactly what you said... However, I feel that if you remove the Haskelly parts from Haskell it's no longer really what makes it so great. I think focus should rather be more on writing better guides (many of the existing ones are not very "hands on" so you can't get straight to doing what you want - web development - even though it's doable). However, that being said, I look forward to seeing how this progresses and anything else you may have in store.
    - friendly_chap 13y ago
      As a beginner I got into Haskell for the basics - generics done right, ADTs, typeclasses, very nice syntax, crazy good list operations etc My reaction to monads & transformers was: "I never asked for this." I got used to them in a couple of weeks but I know multiple people personally who couldn't grasp them in months. I try to provide them with a toolkit to flex their muscles on and be productive with.
egonschiele 13y ago
This looks cool. There's another package for generating html called blaze-html. It's fast and elegant, I like it a lot: http://jaspervdj.be/blaze/ http://jaspervdj.be/blaze/ For parsing HTML, I wrote a library called HandsomeSoup. It adds CSS selectors to HXT, which provides everything you need for parsing HTML: https://github.com/egonschiele/HandsomeSoup https://github.com/egonschiele/HandsomeSoup
- carterschonwald 13y ago
  Blaze is pretty cool. The same author has iterated on a neat static site generator lib that's now in its 4th iteration over the past five years. Likewise, for serious Haskell webdev, Snap, or perhaps HappStack or Yesod, are the tools to consider for general Haskell backed web engineering
Egregore 13y ago
There is also Haquery framework for Haxe language, at http://haquery.com/ http://haquery.com/ As far as I know it's a client server framework (Haxe can be compiled to Javascript and to PHP)
LukeHoersten 13y ago
This might be a nice way to get around the JS-FFI burdening things like Fay and GHCJS which compile Haskell to JS.
Ixiaus 13y ago
Why parsec over attoparsec?

47 points by friendly_chap 13y ago

Hi, author here. Maybe "jQuery for Haskell" is not too descriptive: it is a pure Haskell html dom manipulation tool, mainly useful for templating and/or scraping. It uses the same selectors and API as jQuery, the only deviations are due to immutability (eg. if you modify a selection, the original graph will not be updated of course, so you have to use "alter" or something similar). Edit: Feel free to send a pull request or suggest any changes. The time I poured into the library was mainly focused on getting even the most complex nested selectors to work, because I felt that is the lion's share of the work.

tych0 13y ago
Cool! I have a similar project, based on lift's CssSel's (which are sort of based on the jquery syntax): https://github.com/tych0/hquery https://github.com/tych0/hquery I've been playing around with making a DSL vs. using string based selectors, and I've had little success coming up with something sensible. Have you thought about this at all?
- friendly_chap 13y ago
  I will check your repo too. If you have problems due to similar naming let me know and I will change it. Regarding the selector DSLs, I also went with the string solution, however I translate all selectors to a recursive ADT which could be used directly. Maybe we should unite our powers ;)
  - tych0 13y ago
    Nah, no issues with naming, mine was just a pet project to pick up a bit of haskell. R.E. uniting forces, yeah! I looked through your code a bit, and it looks like we have the same underlying idea (yours seems a bit less convoluted than mine, though :-). I'm not really actively using hquery for anything more than a static site generator I wrote with it, but I wouldn't mind spending a few more hours/week on haskell code.
    - friendly_chap 13y ago
      Seems like we are on the same page, I also test drived this library with a static site generator =). I was really surprised that there are no more templating languages for Haskell given the availability of the mighty parsec. I am following you on github, stay in touch.

alipang 13y ago

Looks cool. I feel like you should try and integrate with existing Haskell concepts. Maybe you'd have to make small changes in the design decisions compared to jQuery, but honestly, using the typical Haskell abstractions things just seem to be "right" somehow. Queries could easily be modelled with the list monad. Add the stateT transformer for effects. Add lenses for niceness. (Lenses could really beautify the internal implementation as well me thinks). I'd love to hear about some of your design choices making this.

friendly_chap 13y ago
Thank you! I definitely agree with you regarding the idiomatic solutions. However, the only defense I can come up with (not that I really want to excuse myself) is this is part of an effort (Hakit) to make Haskell web development accessible to HS beginners. I was a beginner myself when I started Hakit, a web toolkit, and I was overwhelmed by the seemingly complex Haskell APIs. So I tried to build a complete toolkit while forcing the users learning as few Haskell concepts as possible, without writing exceedingly ugly code. I will surely try to make this more appealing to Haskell ninjas too though.
- jhartikainen 13y ago
  Interesting, as a web dev I agree that getting into Haskell can be a bit tricky due to exactly what you said... However, I feel that if you remove the Haskelly parts from Haskell it's no longer really what makes it so great. I think focus should rather be more on writing better guides (many of the existing ones are not very "hands on" so you can't get straight to doing what you want - web development - even though it's doable). However, that being said, I look forward to seeing how this progresses and anything else you may have in store.
  - friendly_chap 13y ago
    As a beginner I got into Haskell for the basics - generics done right, ADTs, typeclasses, very nice syntax, crazy good list operations etc My reaction to monads & transformers was: "I never asked for this." I got used to them in a couple of weeks but I know multiple people personally who couldn't grasp them in months. I try to provide them with a toolkit to flex their muscles on and be productive with.

egonschiele 13y ago

This looks cool. There's another package for generating html called blaze-html. It's fast and elegant, I like it a lot: http://jaspervdj.be/blaze/ http://jaspervdj.be/blaze/ For parsing HTML, I wrote a library called HandsomeSoup. It adds CSS selectors to HXT, which provides everything you need for parsing HTML: https://github.com/egonschiele/HandsomeSoup https://github.com/egonschiele/HandsomeSoup

carterschonwald 13y ago
Blaze is pretty cool. The same author has iterated on a neat static site generator lib that's now in its 4th iteration over the past five years. Likewise, for serious Haskell webdev, Snap, or perhaps HappStack or Yesod, are the tools to consider for general Haskell backed web engineering

Egregore 13y ago

There is also Haquery framework for Haxe language, at http://haquery.com/ http://haquery.com/ As far as I know it's a client server framework (Haxe can be compiled to Javascript and to PHP)

LukeHoersten 13y ago

This might be a nice way to get around the JS-FFI burdening things like Fay and GHCJS which compile Haskell to JS.

Ixiaus 13y ago

Why parsec over attoparsec?