[Haskell-cafe] Possibilities for website construction using Haskell?

[Anton van Straaten]

Don Stewart wrote:
> Note that using string overloading we can remove some of the toHtml's...
> 
>    {-# LANGUAGE OverloadedStrings #-}
> 
>    instance IsString Html where fromString = toHtml
> 
>     main = do
>       time <- getClockTime
> 
>       putStrLn . prettyHtml $
>         (header (thetitle "testing"))
>          +++
>         (body $
>           center $
>              h2 (toHtml (hotlink "http://haskell.org" "Haskell is fun")))
>           +++ show time  

You can also eliminate the toHtmls by using the "<<" operator defined by 
XHTML.  It has type (HTML a) => (Html -> b) -> a -> b, where HTML is a 
type class which has strings, among other things, already defined as 
instances.  So the above can be written as follows, without an 
additional string overloading:

main = do
       time <- getClockTime

       putStrLn . prettyHtml $
         (header (thetitle << "testing"))
          +++
         (body $
           (center $
              h2 << (hotlink "http://haskell.org" << "Haskell is fun"))
           +++ p << show time)

(Wrapping the time in an HTML element like a paragraph allows the use of 
<< to "fill" the paragraph.)

Anton