formula_ternary_operator_node.hpp

// Copyright Take Vos 2020.
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at https://www.boost.org/LICENSE_1_0.txt)
 
#pragma once
 
#include "formula_node.hpp"
 
namespace tt {
 
struct formula_ternary_operator_node final : formula_node {
    std::unique_ptr<formula_node> lhs;
    std::unique_ptr<formula_node> rhs_true;
    std::unique_ptr<formula_node> rhs_false;
 
    formula_ternary_operator_node(parse_location location, std::unique_ptr<formula_node> lhs, std::unique_ptr<formula_node> pair) :
        formula_node(std::move(location)), lhs(std::move(lhs))
    {
        formula_arguments* pair_ = dynamic_cast<formula_arguments*>(pair.get());
        tt_assert(pair_ != nullptr);
        tt_assert(pair_->args.size() == 2);
 
        rhs_true = std::move(pair_->args[0]);
        rhs_false = std::move(pair_->args[1]);
        // The unique_ptrs inside pair_ are now empty.
    }
 
    void post_process(formula_post_process_context& context) override {
        lhs->post_process(context);
        rhs_true->post_process(context);
        rhs_false->post_process(context);
    }
 
    datum evaluate(formula_evaluation_context& context) const override {
        ttlet lhs_ = lhs->evaluate(context);
        if (lhs_) {
            return rhs_true->evaluate(context);
        } else {
            return rhs_false->evaluate(context);
        }
    }
 
    std::string string() const noexcept override {
        return std::format("({} ? {} : {})", *lhs, *rhs_true, *rhs_false);
    }
};
 
}