>> Most ML compilers do this sort of thing to break big blocks of mutually
>> recursive functions into smaller such blocks.  The algorithm used is
>> generally to extract the "strongly connected components" of the graph.
>> Google for it and you'll surely find an algorithm.

> I'm not sure the problem is quite the same though.
> Call graphs are transitive: if A calls B, and B calls C,
> then A calls C.

Right, but the SCC will do the tail/head part of your algorithm in an
"optimal" way, and the strongly connected components can then be cracked
open by adding the t = ex ... x = t thingy.


        Stefan