Re: Pushing the limits [useless]

[Jeff Kingston]

On Wed, 31 Oct 2001 09:37:58 +0100, Samuel Lacas wrote:
  > 
  > Hi,
  > 
  > I was recently re-reading the Lout documentation, and the following
  > sentence (2.3 in Design document) made me smile:
  > 
  >    A programming language may be considered complete when it attains the
  >    power of a Turing machine, but no such criterion seems relevant to
  >    document formatting.
  > 

I believe my intention in writing this sentence was not so much to
comment on the Turing-completeness or otherwise of Lout, but rather
to point to the difficulty of evaluating the satisfactoriness of a
document formatting system, by comparison with a programming language.

My views have modified a bit since then, as I have watched the evolution
of the Eiffel language.  It reached Turing-completeness at the start,
and yet it has evolved steadily ever since; and its type system is
still a mystery.  So now I think that programming languages and document
formatting systems are not as different in that way as I once did.  Lout
struggles to offer features relevant to modelling documents; object-oriented
languages struggle to offer features relevant to modelling objects.  It's
pretty much the same struggle.

Jeff