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#include "cvc4_private.h"
#ifndef __CVC4__THEORY__$id__THEORY_$id_REWRITER_H
#define __CVC4__THEORY__$id__THEORY_$id_REWRITER_H
#include "theory/rewriter.h"
namespace CVC4 {
namespace theory {
namespace $dir {
class Theory$camelRewriter {
public:
/**
* Rewrite a node into the normal form for the theory of $dir.
* Called in post-order (really reverse-topological order) when
* traversing the expression DAG during rewriting. This is the
* main function of the rewriter, and because of the ordering,
* it can assume its children are all rewritten already.
*
* This function can return one of three rewrite response codes
* along with the rewritten node:
*
* REWRITE_DONE indicates that no more rewriting is needed.
* REWRITE_AGAIN means that the top-level expression should be
* rewritten again, but that its children are in final form.
* REWRITE_AGAIN_FULL means that the entire returned expression
* should be rewritten again (top-down with preRewrite(), then
* bottom-up with postRewrite()).
*
* Even if this function returns REWRITE_DONE, if the returned
* expression belongs to a different theory, it will be fully
* rewritten by that theory's rewriter.
*/
static RewriteResponse postRewrite(TNode node) {
// Implement me!
// This default implementation
return RewriteResponse(REWRITE_DONE, node);
}
/**
* Rewrite a node into the normal form for the theory of $dir
* in pre-order (really topological order)---meaning that the
* children may not be in the normal form. This is an optimization
* for theories with cancelling terms (e.g., 0 * (big-nasty-expression)
* in arithmetic rewrites to 0 without the need to look at the big
* nasty expression). Since it's only an optimization, the
* implementation here can do nothing.
*/
static RewriteResponse preRewrite(TNode node) {
// do nothing
return RewriteResponse(REWRITE_DONE, node);
}
/**
* Rewrite an equality, in case special handling is required.
*/
static Node rewriteEquality(TNode equality) {
// often this will suffice
return postRewrite(equality).node;
}
/**
* Initialize the rewriter.
*/
static inline void init() {
// nothing to do
}
/**
* Shut down the rewriter.
*/
static inline void shutdown() {
// nothing to do
}
};/* class Theory$camelRewriter */
}/* CVC4::theory::$dir namespace */
}/* CVC4::theory namespace */
}/* CVC4 namespace */
#endif /* __CVC4__THEORY__$id__THEORY_$id_REWRITER_H */
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