You’ll need hs-twitter, and you can run this as a script like ./jonometer.hs

Now I need to bone up on CouchDB and write version 2!

If you’re new to Haskell,

• [] is the empty list
• [a] is a list with a single element a
• x : y creates a new list by placing element x at the front of list y
• ++ is concatenate
• interact is a function taking a single argument, a function that takes a string and returns a string, and returns a bit of IO that runs the string transformation function on the contents of STDIN and prints the result
• . (period) is a binary operator that composes functions
• foldr is right-fold, and behaves like this: foldr f d [a, b, c] == f a (f b (f c d))
• Lines of the form | a = b are guards, which evaluate to b if a evaluates to True

Example usage:

[/tmp]% cat > header
This is a normal line.
This is a slightly longer line that
  wraps with two spaces.
A short line.
Another example of a long line that
    wraps with tabs (not just once,
    but twice.
Final line.
[/tmp]% cat header | runhaskell Unwrap.hs
This is a normal line.
This is a slightly longer line that wraps with two spaces.
A short line.
Another example of a long line that wraps with tabs (not just once, but twice.
Final line.


Care to share the same program implemented in your language of choice?

Now you can try the Karmic Wallpaper Contest script. Special thanks to Jesse Hallet.