Exit.h

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/*
 * Souffle - A Datalog Compiler
 * Copyright (c) 2013, 2014, Oracle and/or its affiliates. All rights reserved
 * Licensed under the Universal Permissive License v 1.0 as shown at:
 * - https://opensource.org/licenses/UPL
 * - <souffle root>/licenses/SOUFFLE-UPL.txt
 */
 
/************************************************************************
 *
 * @file Exit.h
 *
 ***********************************************************************/
 
#pragma once
 
#include "ram/Condition.h"
#include "ram/Node.h"
#include "ram/Statement.h"
#include "ram/utility/NodeMapper.h"
#include "souffle/utility/ContainerUtil.h"
#include "souffle/utility/MiscUtil.h"
#include "souffle/utility/StreamUtil.h"
#include <cassert>
#include <memory>
#include <ostream>
#include <utility>
#include <vector>
 
namespace souffle::ram {
 
/**
 * @class Exit
 * @brief Exit statement for a loop
 *
 * Exits a loop if exit condition holds.
 *
 * The following example will exit the loop given
 * that A is the empty set:
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~
 * EXIT (A = ∅)
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */
class Exit : public Statement {
public:
    Exit(Own<Condition> c) : condition(std::move(c)) {
        assert(condition && "condition is a nullptr");
    }
 
    /** @brief Get exit condition */
    const Condition& getCondition() const {
        return *condition;
    }
 
    std::vector<const Node*> getChildNodes() const override {
        return {condition.get()};
    }
 
    Exit* clone() const override {
        return new Exit(souffle::clone(condition));
    }
 
    void apply(const NodeMapper& map) override {
        condition = map(std::move(condition));
    }
 
protected:
    void print(std::ostream& os, int tabpos) const override {
        os << times(" ", tabpos) << "EXIT " << getCondition() << std::endl;
    }
 
    bool equal(const Node& node) const override {
        const auto& other = static_cast<const Exit&>(node);
        return equal_ptr(condition, other.condition);
    }
 
    /** Exit condition */
    Own<Condition> condition;
};
 
}  // namespace souffle::ram