1 (* Copyright (C) 2002, HELM Team.
3 * This file is part of HELM, an Hypertextual, Electronic
4 * Library of Mathematics, developed at the Computer Science
5 * Department, University of Bologna, Italy.
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23 * http://cs.unibo.it/helm/.
26 (* Performs a recursive comparisons of the two sides of an equation
27 looking for constructors. If the two sides differ on two constructors,
28 it closes the current goal. If they differ by other two terms it introduces
30 val destruct_tac: term:Cic.term -> ProofEngineTypes.tactic