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[Claudio Sacerdoti Coen <sacerdot AT CS.UniBO.IT>]

> > It makes no difference: I also get `Error: w_Unify'.
 
 You should make a bug-report sending your whole script to the Coq team.
 Recently I investigated Coq unification a bit and found out that often
 w_Unify is raised after some reduction that cross the explicit
 substitutions is involved. It _could_ be such a case.
 
                                        Regards,
                                        C.S.C.

-- 
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Real name: Claudio Sacerdoti Coen
PhD Student in Computer Science at University of Bologna
E-mail: 
sacerdot AT cs.unibo.it
http://caristudenti.cs.unibo.it/~sacerdot
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