HaskellWiki:Syntax highlighting

Syntax highlighting works for a bunch of languages including Haskell, using GeSHi and Jason Dagit's Haskell file, somewhat modified.

Block formatting with <haskell>

To highlight syntax of a block of Haskell, enclose it in <haskell>...</haskell>. This uses the <pre> element. For instance:

{-
My program
-}
import Prelude

foo :: (Monad m) => m (Int,Int)
foo = (x-2,x - 1) where
  x = 3

-- The main function
main :: IO ()
main = do
  a <- foo
  putStr ("And the answer is: " ++(show (fst a))++"\n")

Inline formatting with <hask>

To highlight syntax of inline Haskell snippets, enclose the span in <hask>...</hask>. This uses the <code> element, which is inline. For instance: import Prelude.

Inline highlighting is a bit of a hack at the moment, and may be buggy.

It is indeed, see User:benmachine/hasktag bug --benmachine 01:56, 5 September 2012 (UTC)

I would recommend using the <code> tag instead which seems to do less damage. Though that page that benmachine has linked to now seems fine to me, I've noticed that use of <hask> within a paragraph will result in poor spacing against surrounding paragraphs and <haskell> blocks. Essentially, having <hask> seems to result in the text not being put in a paragraph <p> block -- Michael Jones 13 December 2013

Styles

For Haskell (only) I have deliberately removed all formatting apart from foreground colour, and those I have tried to keep dark so as not to be visually distracting.

This is what I am trying to achieve:

• comments: grey
• keywords (including symbols): blue
• value literals: dark green
• known value identifiers (including symbols): green
• known type identifiers: red
• known classes: purple
• known modules: brown

I also indent the entire block by 2em. See MediaWiki:Common.css.

—Ashley Y 10:49, 19 March 2006 (UTC)

Other languages

This works for certain other languages too. For lisp, for instance, use <pre-lisp>...</pre-lisp> to format a block of lisp, and <code-lisp>...</code-lisp> to format text inline. <haskell> is the same as <pre-haskell> and <hask> is the same as <code-haskell>.