Jean-Christophe Filliatre wrote:

[discussion of programming techniques]

> But writing  an interface is always  a good idea,  since it encourages
> you to  abstract data types and  to provide only  small and orthogonal
> sets of functions, which cannot be done automatically in most cases.

On the other hand, writing the interface _first_ is not always 
appropriate when you want to rapidly prototype experimental code
where you don't actually know what the interface is going to turn
out to be until you experiment.

I often do this, _then_ write an interface, then reimplement
the code cleanly according to this interface. Using this methodology,
I often write the implementation first -- an 'abstraction' of the
interface being in my head:  an easier medium to 'edit' rapidly 
than a text file :-)

-- 
John (Max) Skaller, mailto:skaller@maxtal.com.au
10/1 Toxteth Rd Glebe NSW 2037 Australia voice: 61-2-9660-0850
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