Andy Gill's Html library

24 Jun 2002

      Hi,

I've been working through the source code of Andy Gill's Html library for my 
own edification.
Andrew makes the following definitions.

\begin{code}
instance (Show a) => Show (BlockTable a) where
      showsPrec p = showsTable

type TableI a = [[(a,(Int,Int))]] -> [[(a,(Int,Int))]]

data BlockTable a = Table (Int -> Int -> TableI a) Int Int
\end{code}

You can create a (1x1) table entry

\begin{code}
single :: a -> BlockTable a
single a = Table (\ x y z -> [(a,(x+1,y+1))] : z) 1 1
\end{code}

Can someone explain the reasoning behind using 
a function to describe a Table rather than just a list of lists?

Tom

Andy Gill's Html library

Thomas L. Bevan