[Haskell-cafe] help understanding lazy evaluation

[Xavier Noria]

You people rock. Responses were really helpful and I understand how  
the computation goes now.

I see I need to reprogram my eyes to expect lazy evaluation in places  
where I am used to one-shot results. I see lazy evaluation is all  
around in Haskell builtins.

 From a formal point of view how does this work? The specifications in

   http://www.haskell.org/onlinereport/standard-prelude.html

include the lazy aspect of the definitions albeit they do not require  
that exact implementation, right?

On the other hand, where does Haskell 98 say == is lazy on lists?

-- fxn