dev/get_prepared_statement.h - master - UCS/sqlite_orm

dev/get_prepared_statement.h
172 строки7 KB
klaus triendl
Implemented tuple filtering in terms of operating on index sequences
23 май 2022, 22:36
23 май 2022, 22:36b6d328c
#pragma once

#include <type_traits>  //  std::is_same, std::decay, std::remove_reference

#include "functional/static_magic.h"
#include "prepared_statement.h"
#include "ast_iterator.h"
#include "expression_object_type.h"

namespace sqlite_orm {

    template<int N, class It, class L, class O>
    auto& get(internal::prepared_statement_t<internal::insert_range_t<It, L, O>>& statement) {
        return std::get<N>(statement.expression.range);
    }

    template<int N, class It, class L, class O>
    const auto& get(const internal::prepared_statement_t<internal::insert_range_t<It, L, O>>& statement) {
        return std::get<N>(statement.expression.range);
    }

    template<int N, class It, class L, class O>
    auto& get(internal::prepared_statement_t<internal::replace_range_t<It, L, O>>& statement) {
        return std::get<N>(statement.expression.range);
    }

    template<int N, class It, class L, class O>
    const auto& get(const internal::prepared_statement_t<internal::replace_range_t<It, L, O>>& statement) {
        return std::get<N>(statement.expression.range);
    }

    template<int N, class T, class... Ids>
    auto& get(internal::prepared_statement_t<internal::get_t<T, Ids...>>& statement) {
        return internal::get_ref(std::get<N>(statement.expression.ids));
    }

    template<int N, class T, class... Ids>
    const auto& get(const internal::prepared_statement_t<internal::get_t<T, Ids...>>& statement) {
        return internal::get_ref(std::get<N>(statement.expression.ids));
    }

    template<int N, class T, class... Ids>
    auto& get(internal::prepared_statement_t<internal::get_pointer_t<T, Ids...>>& statement) {
        return internal::get_ref(std::get<N>(statement.expression.ids));
    }

    template<int N, class T, class... Ids>
    const auto& get(const internal::prepared_statement_t<internal::get_pointer_t<T, Ids...>>& statement) {
        return internal::get_ref(std::get<N>(statement.expression.ids));
    }

#ifdef SQLITE_ORM_OPTIONAL_SUPPORTED
    template<int N, class T, class... Ids>
    auto& get(internal::prepared_statement_t<internal::get_optional_t<T, Ids...>>& statement) {
        return internal::get_ref(std::get<N>(statement.expression.ids));
    }

    template<int N, class T, class... Ids>
    const auto& get(const internal::prepared_statement_t<internal::get_optional_t<T, Ids...>>& statement) {
        return internal::get_ref(std::get<N>(statement.expression.ids));
    }
#endif  // SQLITE_ORM_OPTIONAL_SUPPORTED

    template<int N, class T, class... Ids>
    auto& get(internal::prepared_statement_t<internal::remove_t<T, Ids...>>& statement) {
        return internal::get_ref(std::get<N>(statement.expression.ids));
    }

    template<int N, class T, class... Ids>
    const auto& get(const internal::prepared_statement_t<internal::remove_t<T, Ids...>>& statement) {
        return internal::get_ref(std::get<N>(statement.expression.ids));
    }

    template<int N, class T>
    auto& get(internal::prepared_statement_t<internal::update_t<T>>& statement) {
        static_assert(N == 0, "get<> works only with 0 argument for update statement");
        return internal::get_ref(statement.expression.object);
    }

    template<int N, class T>
    const auto& get(const internal::prepared_statement_t<internal::update_t<T>>& statement) {
        static_assert(N == 0, "get<> works only with 0 argument for update statement");
        return internal::get_ref(statement.expression.object);
    }

    template<int N, class T, class... Cols>
    auto& get(internal::prepared_statement_t<internal::insert_explicit<T, Cols...>>& statement) {
        static_assert(N == 0, "get<> works only with 0 argument for insert statement");
        return internal::get_ref(statement.expression.obj);
    }

    template<int N, class T, class... Cols>
    const auto& get(const internal::prepared_statement_t<internal::insert_explicit<T, Cols...>>& statement) {
        static_assert(N == 0, "get<> works only with 0 argument for insert statement");
        return internal::get_ref(statement.expression.obj);
    }

    template<int N, class T>
    auto& get(internal::prepared_statement_t<internal::replace_t<T>>& statement) {
        static_assert(N == 0, "get<> works only with 0 argument for replace statement");
        return internal::get_ref(statement.expression.object);
    }

    template<int N, class T>
    const auto& get(const internal::prepared_statement_t<internal::replace_t<T>>& statement) {
        static_assert(N == 0, "get<> works only with 0 argument for replace statement");
        return internal::get_ref(statement.expression.object);
    }

    template<int N, class T>
    auto& get(internal::prepared_statement_t<internal::insert_t<T>>& statement) {
        static_assert(N == 0, "get<> works only with 0 argument for insert statement");
        return internal::get_ref(statement.expression.object);
    }

    template<int N, class T>
    const auto& get(const internal::prepared_statement_t<internal::insert_t<T>>& statement) {
        static_assert(N == 0, "get<> works only with 0 argument for insert statement");
        return internal::get_ref(statement.expression.object);
    }

    template<int N, class T>
    const auto& get(const internal::prepared_statement_t<T>& statement) {
        using statement_type = std::decay_t<decltype(statement)>;
        using expression_type = typename statement_type::expression_type;
        using node_tuple = internal::node_tuple_t<expression_type>;
        using bind_tuple = internal::bindable_filter_t<node_tuple>;
        using result_type = std::tuple_element_t<static_cast<size_t>(N), bind_tuple>;
        const result_type* result = nullptr;
        internal::iterate_ast(statement.expression, [&result, index = -1](auto& node) mutable {
            using node_type = std::decay_t<decltype(node)>;
            if(internal::is_bindable_v<node_type>) {
                ++index;
            }
            if(index == N) {
                internal::call_if_constexpr<std::is_same<result_type, node_type>::value>(
                    [](auto& r, auto& n) {
                        r = &n;
                    },
                    result,
                    node);
            }
        });
        return internal::get_ref(*result);
    }

    template<int N, class T>
    auto& get(internal::prepared_statement_t<T>& statement) {
        using statement_type = std::decay_t<decltype(statement)>;
        using expression_type = typename statement_type::expression_type;
        using node_tuple = internal::node_tuple_t<expression_type>;
        using bind_tuple = internal::bindable_filter_t<node_tuple>;
        using result_type = std::tuple_element_t<static_cast<size_t>(N), bind_tuple>;
        result_type* result = nullptr;

        internal::iterate_ast(statement.expression, [&result, index = -1](auto& node) mutable {
            using node_type = std::decay_t<decltype(node)>;
            if(internal::is_bindable_v<node_type>) {
                ++index;
            }
            if(index == N) {
                internal::call_if_constexpr<std::is_same<result_type, node_type>::value>(
                    [](auto& r, auto& n) {
                        r = const_cast<std::remove_reference_t<decltype(r)>>(&n);
                    },
                    result,
                    node);
            }
        });
        return internal::get_ref(*result);
    }
}