On Mon, 2005-02-07 at 09:26, Radu Grigore wrote:
> Do you have an example where forking lineages
> is useful? 

Sure -- in a compiler a Map representing the symbol table
works well with recusive analysis, since when you
pop out of a scope, the symbols in the old scope
just 'remain' as they were and the ones added
in the inner scope just 'disappear'.

I use this feature of lists to analyse graphs
using recursive descent all the time, using
the list to track the current path to prevent
infinite recursion by identifying uplinks
(weak pointers).

So yes, the persistence is very useful in a wide
variety of circumstances.

I dare say, database programmers would kill for
a functional database .. of course programmers
have been using CVS for a while .. even C++ people :)

-- 
John Skaller, mailto:skaller@users.sf.net
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