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/*++
Copyright (c) 2012 Microsoft Corporation
Module Name:
der_tactic.h
Abstract:
DER tactic
Author:
Leonardo de Moura (leonardo) 2012-10-20
Tactic Documentation:
## Tactic der
### Short Description:
The tactic performs _destructive equality resolution_.
### Long Description
Destructive equality resolution replaces bound variables that are
_solved_ by their solutions in formulas. In short, the destructive
equality resolution rule takes the form:
```
(forall (X Y) (or X /= s C[X])) --> (forall (Y) C[Y])
```
### Example
```z3
(declare-fun f (Int) Int)
(declare-fun p (Int Int) Bool)
(assert (forall ((x Int) (y Int)) (or (not (= x (f y))) (p x y))))
(apply der)
```
### Notes
* supports unsat cores, proof terms
--*/
#pragma once
class ast_manager;
class tactic;
tactic * mk_der_tactic(ast_manager & m);
/*
ADD_TACTIC("der", "destructive equality resolution.", "mk_der_tactic(m)")
*/