tomlplusplus/include/toml++/toml_node.h
Mark Gillard fd07301bae improved support for __fp16, _Float16 and __float128
also:
- fixed a bunch of doxygen parsing issues
- added `#define` leak detection to the single-header script
- renamed `TOML_ALL_INLINE` to `TOML_HEADER_ONLY` (the old one still works too)
- simplified abi namespace definitions
2020-07-25 20:50:24 +03:00

725 lines
26 KiB
C++

//# This file is a part of toml++ and is subject to the the terms of the MIT license.
//# Copyright (c) 2019-2020 Mark Gillard <mark.gillard@outlook.com.au>
//# See https://github.com/marzer/tomlplusplus/blob/master/LICENSE for the full license text.
// SPDX-License-Identifier: MIT
#pragma once
#include "toml_common.h"
TOML_PUSH_WARNINGS
TOML_DISABLE_PADDING_WARNINGS
TOML_DISABLE_MISC_WARNINGS
#if TOML_SIMPLE_STATIC_ASSERT_MESSAGES
#define TOML_SA_NEWLINE " "
#define TOML_SA_LIST_SEP ", "
#define TOML_SA_LIST_BEG " ("
#define TOML_SA_LIST_END ")"
#define TOML_SA_LIST_NEW " "
#define TOML_SA_LIST_NXT ", "
#define TOML_SA_LIST_CAP(...)
#else
#define TOML_SA_NEWLINE "\n| "
#define TOML_SA_LIST_SEP TOML_SA_NEWLINE " - "
#define TOML_SA_LIST_BEG TOML_SA_LIST_SEP
#define TOML_SA_LIST_END
#define TOML_SA_LIST_NEW TOML_SA_NEWLINE TOML_SA_NEWLINE
#define TOML_SA_LIST_NXT TOML_SA_LIST_NEW
#define TOML_SA_LIST_CAP(val) val
#endif
#define TOML_SA_NATIVE_VALUE_TYPE_LIST \
TOML_SA_LIST_BEG "std::string" \
TOML_SA_LIST_SEP "int64_t" \
TOML_SA_LIST_SEP "double" \
TOML_SA_LIST_SEP "bool" \
TOML_SA_LIST_SEP "toml::date" \
TOML_SA_LIST_SEP "toml::time" \
TOML_SA_LIST_SEP "toml::date_time" \
TOML_SA_LIST_END
#define TOML_SA_NODE_TYPE_LIST \
TOML_SA_LIST_BEG "toml::table" \
TOML_SA_LIST_SEP "toml::array" \
TOML_SA_LIST_SEP "toml::value<std::string>" \
TOML_SA_LIST_SEP "toml::value<int64_t>" \
TOML_SA_LIST_SEP "toml::value<double>" \
TOML_SA_LIST_SEP "toml::value<bool>" \
TOML_SA_LIST_SEP "toml::value<toml::date>" \
TOML_SA_LIST_SEP "toml::value<toml::time>" \
TOML_SA_LIST_SEP "toml::value<toml::date_time>" \
TOML_SA_LIST_END
#define TOML_SA_UNWRAPPED_NODE_TYPE_LIST \
TOML_SA_LIST_NEW "A native TOML value type" \
TOML_SA_NATIVE_VALUE_TYPE_LIST \
\
TOML_SA_LIST_NXT "A TOML node type" \
TOML_SA_NODE_TYPE_LIST
TOML_NAMESPACE_START
{
/// \brief A TOML node.
///
/// \detail A parsed TOML document forms a tree made up of tables, arrays and values.
/// This type is the base of each of those, providing a lot of the polymorphic plumbing.
class TOML_INTERFACE TOML_API node
{
private:
friend class TOML_PARSER_TYPENAME;
source_region source_{};
protected:
node(node&& other) noexcept;
node& operator= (node&& rhs) noexcept;
template <typename T>
[[nodiscard]]
TOML_ALWAYS_INLINE
impl::wrap_node<T>& ref_cast() & noexcept
{
return *reinterpret_cast<impl::wrap_node<T>*>(this);
}
template <typename T>
[[nodiscard]]
TOML_ALWAYS_INLINE
impl::wrap_node<T>&& ref_cast() && noexcept
{
return std::move(*reinterpret_cast<impl::wrap_node<T>*>(this));
}
template <typename T>
[[nodiscard]]
TOML_ALWAYS_INLINE
const impl::wrap_node<T>& ref_cast() const & noexcept
{
return *reinterpret_cast<const impl::wrap_node<T>*>(this);
}
template <typename N, typename T>
using ref_cast_type = decltype(std::declval<N>().template ref_cast<T>());
node() noexcept = default;
node(const node&) = delete;
node& operator= (const node&) = delete;
public:
virtual ~node() noexcept = default;
/// \brief Returns the node's type identifier.
[[nodiscard]] virtual node_type type() const noexcept = 0;
/// \brief Returns true if this node is a table.
[[nodiscard]] virtual bool is_table() const noexcept = 0;
/// \brief Returns true if this node is an array.
[[nodiscard]] virtual bool is_array() const noexcept = 0;
/// \brief Returns true if this node is a value.
[[nodiscard]] virtual bool is_value() const noexcept = 0;
/// \brief Returns true if this node is a string value.
[[nodiscard]] virtual bool is_string() const noexcept;
/// \brief Returns true if this node is an integer value.
[[nodiscard]] virtual bool is_integer() const noexcept;
/// \brief Returns true if this node is an floating-point value.
[[nodiscard]] virtual bool is_floating_point() const noexcept;
/// \brief Returns true if this node is an integer or floating-point value.
[[nodiscard]] virtual bool is_number() const noexcept;
/// \brief Returns true if this node is a boolean value.
[[nodiscard]] virtual bool is_boolean() const noexcept;
/// \brief Returns true if this node is a local date value.
[[nodiscard]] virtual bool is_date() const noexcept;
/// \brief Returns true if this node is a local time value.
[[nodiscard]] virtual bool is_time() const noexcept;
/// \brief Returns true if this node is a date-time value.
[[nodiscard]] virtual bool is_date_time() const noexcept;
/// \brief Returns true if this node is an array containing only tables.
[[nodiscard]] virtual bool is_array_of_tables() const noexcept;
/// \brief Checks if a node is a specific type.
///
/// \tparam T A TOML node or value type.
///
/// \returns Returns true if this node is an instance of the specified type.
template <typename T>
[[nodiscard]]
bool is() const noexcept
{
using type = impl::unwrap_node<T>;
static_assert(
(impl::is_native<type> || impl::is_one_of<type, table, array>) && !impl::is_cvref<type>,
"The template type argument of node::is() must be one of:"
TOML_SA_UNWRAPPED_NODE_TYPE_LIST
);
if constexpr (std::is_same_v<type, table>) return is_table();
else if constexpr (std::is_same_v<type, array>) return is_array();
else if constexpr (std::is_same_v<type, std::string>) return is_string();
else if constexpr (std::is_same_v<type, int64_t>) return is_integer();
else if constexpr (std::is_same_v<type, double>) return is_floating_point();
else if constexpr (std::is_same_v<type, bool>) return is_boolean();
else if constexpr (std::is_same_v<type, date>) return is_date();
else if constexpr (std::is_same_v<type, time>) return is_time();
else if constexpr (std::is_same_v<type, date_time>) return is_date_time();
}
/// \brief Returns a pointer to the node as a toml::table, if it is one.
[[nodiscard]] virtual table* as_table() noexcept;
/// \brief Returns a pointer to the node as a toml::array, if it is one.
[[nodiscard]] virtual array* as_array() noexcept;
/// \brief Returns a pointer to the node as a toml::value<string>, if it is one.
[[nodiscard]] virtual toml::value<std::string>* as_string() noexcept;
/// \brief Returns a pointer to the node as a toml::value<int64_t>, if it is one.
[[nodiscard]] virtual toml::value<int64_t>* as_integer() noexcept;
/// \brief Returns a pointer to the node as a toml::value<double>, if it is one.
[[nodiscard]] virtual toml::value<double>* as_floating_point() noexcept;
/// \brief Returns a pointer to the node as a toml::value<bool>, if it is one.
[[nodiscard]] virtual toml::value<bool>* as_boolean() noexcept;
/// \brief Returns a pointer to the node as a toml::value<date>, if it is one.
[[nodiscard]] virtual toml::value<date>* as_date() noexcept;
/// \brief Returns a pointer to the node as a toml::value<time>, if it is one.
[[nodiscard]] virtual toml::value<time>* as_time() noexcept;
/// \brief Returns a pointer to the node as a toml::value<date_time>, if it is one.
[[nodiscard]] virtual toml::value<date_time>* as_date_time() noexcept;
[[nodiscard]] virtual const table* as_table() const noexcept;
[[nodiscard]] virtual const array* as_array() const noexcept;
[[nodiscard]] virtual const toml::value<std::string>* as_string() const noexcept;
[[nodiscard]] virtual const toml::value<int64_t>* as_integer() const noexcept;
[[nodiscard]] virtual const toml::value<double>* as_floating_point() const noexcept;
[[nodiscard]] virtual const toml::value<bool>* as_boolean() const noexcept;
[[nodiscard]] virtual const toml::value<date>* as_date() const noexcept;
[[nodiscard]] virtual const toml::value<time>* as_time() const noexcept;
[[nodiscard]] virtual const toml::value<date_time>* as_date_time() const noexcept;
private:
#ifndef DOXYGEN
template <typename T>
[[nodiscard]]
decltype(auto) get_value_exact() const noexcept;
#endif // !DOXYGEN
public:
/// \brief Gets the value contained by this node.
///
/// \detail This function has 'exact' retrieval semantics; the only return value types allowed are the
/// TOML native value types, or types that can losslessly represent a native value type (e.g.
/// std::wstring on Windows).
///
/// \tparam T One of the native TOML value types, or a type capable of losslessly representing one.
///
/// \returns The underlying value if the node was a value of the
/// matching type (or losslessly convertible to it), or an empty optional.
///
/// \see node::value()
template <typename T>
[[nodiscard]]
optional<T> value_exact() const noexcept;
/// \brief Gets the value contained by this node.
///
/// \detail This function has 'permissive' retrieval semantics; some value types are allowed
/// to convert to others (e.g. retrieving a boolean as an integer), and the specified return value
/// type can be any type where a reasonable conversion from a native TOML value exists
/// (e.g. std::wstring on Windows). If the source value cannot be represented by
/// the destination type, an empty optional is returned.
///
/// \cpp
/// auto tbl = toml::parse(R"(
/// int = -10
/// flt = 25.0
/// pi = 3.14159
/// bool = false
/// huge = 9223372036854775807
/// str = "foo"
/// )"sv);
///
/// const auto print_value_with_typename =
/// [&](std::string_view key, std::string_view type_name, auto* dummy)
/// {
/// std::cout << "'" << key << "' as " << type_name << ": ";
/// using type = std::remove_pointer_t<decltype(dummy)>;
/// if (std::optional<type> val = tbl.get(key)->value<type>())
/// std::cout << *val << "\n";
/// else
/// std::cout << "No conversion path or out-of-range\n";
/// };
///
/// #define print_value(key, T) print_value_with_typename(key, #T, (T*)nullptr)
///
/// print_value("int", bool);
/// print_value("int", int);
/// print_value("int", unsigned int);
/// print_value("int", long long);
/// print_value("int", float);
/// print_value("int", double);
/// std::cout << "\n";
///
/// print_value("flt", bool);
/// print_value("flt", int);
/// print_value("flt", unsigned int);
/// print_value("flt", long long);
/// print_value("flt", float);
/// print_value("flt", double);
/// std::cout << "\n";
///
/// print_value("pi", bool);
/// print_value("pi", int);
/// print_value("pi", unsigned int);
/// print_value("pi", long long);
/// print_value("pi", float);
/// print_value("pi", double);
/// std::cout << "\n";
///
/// print_value("bool", bool);
/// print_value("bool", int);
/// print_value("bool", unsigned int);
/// print_value("bool", long long);
/// print_value("bool", float);
/// print_value("bool", double);
/// std::cout << "\n";
///
/// print_value("huge", bool);
/// print_value("huge", int);
/// print_value("huge", unsigned int);
/// print_value("huge", long long);
/// print_value("huge", float);
/// print_value("huge", double);
/// std::cout << "\n";
///
/// print_value("str", std::string);
/// print_value("str", std::string_view);
/// print_value("str", const char*);
/// std::cout << "\n";
/// \ecpp
///
/// \out
/// 'int' as bool: true
/// 'int' as int: -10
/// 'int' as unsigned int: No conversion path or out-of-range
/// 'int' as long long: -10
/// 'int' as float: -10
/// 'int' as double: -10
///
/// 'flt' as bool: No conversion path or out-of-range
/// 'flt' as int: 25
/// 'flt' as unsigned int: 25
/// 'flt' as long long: 25
/// 'flt' as float: 25
/// 'flt' as double: 25
///
/// 'pi' as bool: No conversion path or out-of-range
/// 'pi' as int: No conversion path or out-of-range
/// 'pi' as unsigned int: No conversion path or out-of-range
/// 'pi' as long long: No conversion path or out-of-range
/// 'pi' as float: 3.14159
/// 'pi' as double: 3.14159
///
/// 'bool' as bool: false
/// 'bool' as int: 0
/// 'bool' as unsigned int: 0
/// 'bool' as long long: 0
/// 'bool' as float: No conversion path or out-of-range
/// 'bool' as double: No conversion path or out-of-range
///
/// 'huge' as bool: true
/// 'huge' as int: No conversion path or out-of-range
/// 'huge' as unsigned int: No conversion path or out-of-range
/// 'huge' as long long: 9223372036854775807
/// 'huge' as float: No conversion path or out-of-range
/// 'huge' as double: No conversion path or out-of-range
///
/// 'str' as std::string: foo
/// 'str' as std::string_view: foo
/// 'str' as const char*: foo
/// \eout
///
/// \tparam T One of the native TOML value types, or a type capable of converting to one.
///
/// \returns The underlying value if the node was a value of the matching type (or convertible to it)
/// and within the range of the output type, or an empty optional.
///
/// \attention If you want strict value retrieval semantics that do not allow for any type conversions,
/// use node::value_exact() instead.
///
/// \see node::value_exact()
template <typename T>
[[nodiscard]]
optional<T> value() const noexcept;
/// \brief Gets the raw value contained by this node, or a default.
///
/// \tparam T Default value type. Must be one of the native TOML value types,
/// or convertible to it.
/// \param default_value The default value to return if the node wasn't a value, wasn't the
/// correct type, or no conversion was possible.
///
/// \returns The underlying value if the node was a value of the matching type (or convertible to it)
/// and within the range of the output type, or the provided default.
///
/// \attention This function has the same permissive retrieval semantics as node::value(). If you want strict
/// value retrieval semantics that do not allow for any type conversions, use node::value_exact()
/// instead.
///
/// \see
/// - node::value()
/// - node::value_exact()
template <typename T>
[[nodiscard]]
auto value_or(T&& default_value) const noexcept;
/// \brief Gets a pointer to the node as a more specific node type.
///
/// \details \cpp
///
/// toml::value<int64_t>* int_value = node->as<int64_t>();
/// toml::table* tbl = node->as<toml::table>();
/// if (int_value)
/// std::cout << "Node is a value<int64_t>" << std::endl;
/// else if (tbl)
/// std::cout << "Node is a table" << std::endl;
///
/// // fully-qualified value node types also work (useful for template code):
/// toml::value<int64_t>* int_value2 = node->as<toml::value<int64_t>>();
/// if (int_value2)
/// std::cout << "Node is a value<int64_t>" << std::endl;
///
/// \ecpp
///
/// \tparam T The node type or TOML value type to cast to.
///
/// \returns A pointer to the node as the given type, or nullptr if it was a different type.
template <typename T>
[[nodiscard]]
impl::wrap_node<T>* as() noexcept
{
using type = impl::unwrap_node<T>;
static_assert(
(impl::is_native<type> || impl::is_one_of<type, table, array>) && !impl::is_cvref<type>,
"The template type argument of node::as() must be one of:"
TOML_SA_UNWRAPPED_NODE_TYPE_LIST
);
if constexpr (std::is_same_v<type, table>) return as_table();
else if constexpr (std::is_same_v<type, array>) return as_array();
else if constexpr (std::is_same_v<type, std::string>) return as_string();
else if constexpr (std::is_same_v<type, int64_t>) return as_integer();
else if constexpr (std::is_same_v<type, double>) return as_floating_point();
else if constexpr (std::is_same_v<type, bool>) return as_boolean();
else if constexpr (std::is_same_v<type, date>) return as_date();
else if constexpr (std::is_same_v<type, time>) return as_time();
else if constexpr (std::is_same_v<type, date_time>) return as_date_time();
}
/// \brief Gets a pointer to the node as a more specific node type (const overload).
template <typename T>
[[nodiscard]]
const impl::wrap_node<T>* as() const noexcept
{
using type = impl::unwrap_node<T>;
static_assert(
(impl::is_native<type> || impl::is_one_of<type, table, array>) && !impl::is_cvref<type>,
"The template type argument of node::as() must be one of:"
TOML_SA_UNWRAPPED_NODE_TYPE_LIST
);
if constexpr (std::is_same_v<type, table>) return as_table();
else if constexpr (std::is_same_v<type, array>) return as_array();
else if constexpr (std::is_same_v<type, std::string>) return as_string();
else if constexpr (std::is_same_v<type, int64_t>) return as_integer();
else if constexpr (std::is_same_v<type, double>) return as_floating_point();
else if constexpr (std::is_same_v<type, bool>) return as_boolean();
else if constexpr (std::is_same_v<type, date>) return as_date();
else if constexpr (std::is_same_v<type, time>) return as_time();
else if constexpr (std::is_same_v<type, date_time>) return as_date_time();
}
/// \brief Returns the source region responsible for generating this node during parsing.
[[nodiscard]] const source_region& source() const noexcept;
private:
template <typename Func, typename N, typename T>
static constexpr bool can_visit = std::is_invocable_v<Func, ref_cast_type<N, T>>;
template <typename Func, typename N>
static constexpr bool can_visit_any =
can_visit<Func, N, table>
|| can_visit<Func, N, array>
|| can_visit<Func, N, std::string>
|| can_visit<Func, N, int64_t>
|| can_visit<Func, N, double>
|| can_visit<Func, N, bool>
|| can_visit<Func, N, date>
|| can_visit<Func, N, time>
|| can_visit<Func, N, date_time>;
template <typename Func, typename N>
static constexpr bool can_visit_all =
can_visit<Func, N, table>
&& can_visit<Func, N, array>
&& can_visit<Func, N, std::string>
&& can_visit<Func, N, int64_t>
&& can_visit<Func, N, double>
&& can_visit<Func, N, bool>
&& can_visit<Func, N, date>
&& can_visit<Func, N, time>
&& can_visit<Func, N, date_time>;
template <typename Func, typename N, typename T>
static constexpr bool visit_is_nothrow_one =
!can_visit<Func, N, T>
|| std::is_nothrow_invocable_v<Func, ref_cast_type<N, T>>;
template <typename Func, typename N>
static constexpr bool visit_is_nothrow =
visit_is_nothrow_one<Func, N, table>
&& visit_is_nothrow_one<Func, N, array>
&& visit_is_nothrow_one<Func, N, std::string>
&& visit_is_nothrow_one<Func, N, int64_t>
&& visit_is_nothrow_one<Func, N, double>
&& visit_is_nothrow_one<Func, N, bool>
&& visit_is_nothrow_one<Func, N, date>
&& visit_is_nothrow_one<Func, N, time>
&& visit_is_nothrow_one<Func, N, date_time>;
template <typename Func, typename N, typename T, bool = can_visit<Func, N, T>>
struct visit_return_type final
{
using type = decltype(std::declval<Func>()(std::declval<ref_cast_type<N, T>>()));
};
template <typename Func, typename N, typename T>
struct visit_return_type<Func, N, T, false> final
{
using type = void;
};
template <typename A, typename B>
using nonvoid = std::conditional_t<std::is_void_v<A>, B, A>;
//# these functions are static helpers to preserve const and ref categories
//# (otherwise I'd have to implement them thrice)
//# ((propagation in C++: a modern horror story))
template <typename N, typename Func>
static decltype(auto) do_visit(N&& n, Func&& visitor)
noexcept(visit_is_nothrow<Func&&, N&&>)
{
static_assert(
can_visit_any<Func&&, N&&>,
"TOML node visitors must be invocable for at least one of the toml::node specializations:"
TOML_SA_NODE_TYPE_LIST
);
switch (n.type())
{
case node_type::table:
if constexpr (can_visit<Func&&, N&&, table>)
return std::forward<Func>(visitor)(std::forward<N>(n).template ref_cast<table>());
break;
case node_type::array:
if constexpr (can_visit<Func&&, N&&, array>)
return std::forward<Func>(visitor)(std::forward<N>(n).template ref_cast<array>());
break;
case node_type::string:
if constexpr (can_visit<Func&&, N&&, std::string>)
return std::forward<Func>(visitor)(std::forward<N>(n).template ref_cast<std::string>());
break;
case node_type::integer:
if constexpr (can_visit<Func&&, N&&, int64_t>)
return std::forward<Func>(visitor)(std::forward<N>(n).template ref_cast<int64_t>());
break;
case node_type::floating_point:
if constexpr (can_visit<Func&&, N&&, double>)
return std::forward<Func>(visitor)(std::forward<N>(n).template ref_cast<double>());
break;
case node_type::boolean:
if constexpr (can_visit<Func&&, N&&, bool>)
return std::forward<Func>(visitor)(std::forward<N>(n).template ref_cast<bool>());
break;
case node_type::date:
if constexpr (can_visit<Func&&, N&&, date>)
return std::forward<Func>(visitor)(std::forward<N>(n).template ref_cast<date>());
break;
case node_type::time:
if constexpr (can_visit<Func&&, N&&, time>)
return std::forward<Func>(visitor)(std::forward<N>(n).template ref_cast<time>());
break;
case node_type::date_time:
if constexpr (can_visit<Func&&, N&&, date_time>)
return std::forward<Func>(visitor)(std::forward<N>(n).template ref_cast<date_time>());
break;
case node_type::none: TOML_UNREACHABLE;
TOML_NO_DEFAULT_CASE;
}
if constexpr (can_visit_all<Func&&, N&&>)
TOML_UNREACHABLE;
else
{
using return_type =
nonvoid<typename visit_return_type<Func&&, N&&, table>::type,
nonvoid<typename visit_return_type<Func&&, N&&, array>::type,
nonvoid<typename visit_return_type<Func&&, N&&, std::string>::type,
nonvoid<typename visit_return_type<Func&&, N&&, int64_t>::type,
nonvoid<typename visit_return_type<Func&&, N&&, double>::type,
nonvoid<typename visit_return_type<Func&&, N&&, bool>::type,
nonvoid<typename visit_return_type<Func&&, N&&, date>::type,
nonvoid<typename visit_return_type<Func&&, N&&, time>::type,
typename visit_return_type<Func&&, N&&, date_time>::type
>>>>>>>>;
if constexpr (!std::is_void_v<return_type>)
{
static_assert(
std::is_default_constructible_v<return_type>,
"Non-exhaustive visitors must return a default-constructible type, or void"
);
return return_type{};
}
}
}
template <typename T, typename N>
[[nodiscard]]
static decltype(auto) do_ref(N&& n) noexcept
{
using type = impl::unwrap_node<T>;
static_assert(
(impl::is_native<type> || impl::is_one_of<type, table, array>) && !impl::is_cvref<type>,
"The template type argument of node::ref() must be one of:"
TOML_SA_UNWRAPPED_NODE_TYPE_LIST
);
TOML_ASSERT(
n.template is<T>()
&& "template type argument T provided to toml::node::ref() didn't match the node's actual type"
);
if constexpr (impl::is_native<type>)
return std::forward<N>(n).template ref_cast<type>().get();
else
return std::forward<N>(n).template ref_cast<type>();
}
public:
/// \brief Invokes a visitor on the node based on the node's concrete type.
///
/// \details Visitation is useful when you expect
/// a node to be one of a set number of types and need
/// to handle these types differently. Using `visit()` allows
/// you to eliminate some of the casting/conversion boilerplate: \cpp
///
/// node.visit([](auto&& n)
/// {
/// if constexpr (toml::is_string<decltype(n)>)
/// do_something_with_a_string(*n)); //n is a toml::value<std::string>
/// else if constexpr (toml::is_integer<decltype(n)>)
/// do_something_with_an_int(*n); //n is a toml::value<int64_t>
/// else
/// throw std::exception{ "Expected string or integer" };
/// });
///
/// \ecpp
///
/// \tparam Func A callable type invocable with one or more of the
/// toml++ node types.
///
/// \param visitor The visitor object.
///
/// \returns The return value of the visitor.
/// Can be void. Non-exhaustive visitors must return a default-constructible type.
///
/// \see https://en.wikipedia.org/wiki/Visitor_pattern
template <typename Func>
decltype(auto) visit(Func&& visitor) &
noexcept(visit_is_nothrow<Func&&, node&>)
{
return do_visit(*this, std::forward<Func>(visitor));
}
/// \brief Invokes a visitor on the node based on the node's concrete type (rvalue overload).
template <typename Func>
decltype(auto) visit(Func&& visitor) &&
noexcept(visit_is_nothrow<Func&&, node&&>)
{
return do_visit(std::move(*this), std::forward<Func>(visitor));
}
/// \brief Invokes a visitor on the node based on the node's concrete type (const lvalue overload).
template <typename Func>
decltype(auto) visit(Func&& visitor) const&
noexcept(visit_is_nothrow<Func&&, const node&>)
{
return do_visit(*this, std::forward<Func>(visitor));
}
/// \brief Gets a raw reference to a value node's underlying data.
///
/// \warning This function is dangerous if used carelessly and **WILL** break your code if the
/// chosen value type doesn't match the node's actual type. In debug builds an assertion
/// will fire when invalid accesses are attempted: \cpp
///
/// auto tbl = toml::parse(R"(
/// min = 32
/// max = 45
/// )"sv);
///
/// int64_t& min_ref = tbl.get("min")->ref<int64_t>(); // matching type
/// double& max_ref = tbl.get("max")->ref<double>(); // mismatched type, hits assert()
///
/// \ecpp
///
/// \tparam T One of the TOML value types.
///
/// \returns A reference to the underlying data.
template <typename T>
[[nodiscard]]
impl::unwrap_node<T>& ref() & noexcept
{
return do_ref<T>(*this);
}
/// \brief Gets a raw reference to a value node's underlying data (rvalue overload).
template <typename T>
[[nodiscard]]
impl::unwrap_node<T>&& ref() && noexcept
{
return do_ref<T>(std::move(*this));
}
/// \brief Gets a raw reference to a value node's underlying data (const lvalue overload).
template <typename T>
[[nodiscard]]
const impl::unwrap_node<T>& ref() const& noexcept
{
return do_ref<T>(*this);
}
};
}
TOML_NAMESPACE_END
TOML_POP_WARNINGS // TOML_DISABLE_PADDING_WARNINGS, TOML_DISABLE_MISC_WARNINGS