Comments on: Simple Haskell Web Programming with HAppS

By: How to Install HAppS - bluebones.net

How to Install HAppS - bluebones.net — Sun, 06 Jan 2008 14:32:50 +0000

[...] Update: the rest of the HAppS tutorial was fairly dense and difficult to understand as well as being somewhat out of date. To remedy this situation I wrote Simple Haskell Web Programming with HAppS. [...]

By: Jerry

Jerry — Tue, 02 Oct 2007 22:50:28 +0000

Thanks for a nice example. I have been very intrigued by HAppS for a while but have constantly been put off by the confusing, missing, outdated, and sometimes wrong documentation. The questions that get asked on the HAppS mailing list go flying over my head. I’ve been search for something between broken tutorial and esoteric questions, and your refreshing example fits the bill nicely! Thanks!

By: Thomas David Baker

Thomas David Baker — Tue, 02 Oct 2007 15:58:09 +0000

Thanks Manu, I’ve corrected those too. Apparently wordpress doesn’t like less than symbols.

By: manu

manu — Tue, 02 Oct 2007 14:27:11 +0000

oops it got chomped

A few more correction to get the last example to compile :

line 35 : < – should be <-
line 76 & 80 : < < should be <<

otherwise it works, thanks for the tutorial !

By: manu

manu — Tue, 02 Oct 2007 14:25:31 +0000

A few more correction to get the last example to compile :

line 35 :

By: Thomas David Baker

Thomas David Baker — Mon, 01 Oct 2007 19:10:46 +0000

Sorry Manu bit of an escape character failure there. This line:

,h (re ["post", "([0-9]+)"])  GET  $ ok $ (id:_) () -> respond ("Display post " ++ id)

should be:

,h (re ["post", "([0-9]+)"])  GET  $ ok $ \\(id:_) () -> respond ("Display post " ++ id)

(that's a haskell lambda expression for a function with two arguments the first of which is a list and the second is null). I've corrected it in the article. Thanks!

By: manu

manu — Mon, 01 Oct 2007 17:38:35 +0000

this snippet :

main = stdHTTP $ debugFilter : noState : 
           [h ["new"]                           GET  $ ok $ val "Show create post form"
           ,h ["new"]                           POST $ ok $ val "Save post and forward to display post"
           ,h (re ["post", "([0-9]+)"])  GET  $ ok $ (id:_) () -> respond ("Display post " ++ id)
           ,h [""]                              GET  $ ok $ val "Display five most recent posts"
           ]

refuse to compile :

[1 of 1] Compiling Main             ( Hello.hs, Hello.o )

Hello.hs:9:63: parse error on input `->'

By: Thomas David Baker

Thomas David Baker — Sun, 30 Sep 2007 21:18:42 +0000

Hey, if it’s not Haskell compiled down to javascript then we don’t want to know!

By: Jonathan Aquino

Jonathan Aquino — Sun, 30 Sep 2007 18:55:06 +0000

Ah shoot, it stripped out my code – anyway I just pasted in the snippet from http://js-kit.com/comments/

By: Jonathan Aquino

Jonathan Aquino — Sun, 30 Sep 2007 18:54:19 +0000

Here’s how to add comments with one line of code