1853 lines
62 KiB
C++
1853 lines
62 KiB
C++
/*
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* Copyright (c) 2021-2022 Bowen Fu
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* Distributed Under The Apache-2.0 License
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*/
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#ifndef MATCHIT_H
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#define MATCHIT_H
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#ifndef MATCHIT_CORE_H
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#define MATCHIT_CORE_H
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#include <algorithm>
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#include <cstdint>
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#include <tuple>
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namespace matchit {
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// NOLINTBEGIN(*-identifier-naming)
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namespace impl {
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template <typename Value, bool byRef>
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class ValueType {
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public:
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using ValueT = Value;
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};
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template <typename Value>
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class ValueType<Value, true> {
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public:
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using ValueT = Value&&;
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};
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template <typename Value, typename... Patterns>
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constexpr auto matchPatterns(Value&& value, const Patterns&... patterns);
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template <typename Value, bool byRef>
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class MatchHelper {
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private:
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using ValueT = typename ValueType<Value, byRef>::ValueT;
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ValueT mValue;
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using ValueRefT = ValueT&&;
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public:
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template <typename V>
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constexpr explicit MatchHelper(V&& value)
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: mValue { std::forward<V>(value) } {}
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template <typename... PatternPair>
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constexpr auto operator()(const PatternPair&... patterns) {
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return matchPatterns(std::forward<ValueRefT>(mValue), patterns...);
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}
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};
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template <typename Value>
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constexpr auto match(Value&& value) {
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return MatchHelper<Value, true> { std::forward<Value>(value) };
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}
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template <typename First, typename... Values>
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constexpr auto match(First&& first, Values&&... values) {
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auto result = std::forward_as_tuple(std::forward<First>(first), std::forward<Values>(values)...);
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return MatchHelper<decltype(result), false> { std::forward<decltype(result)>(result) };
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}
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} // namespace impl
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// export symbols
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using impl::match;
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} // namespace matchit
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#endif // MATCHIT_CORE_H
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#ifndef MATCHIT_EXPRESSION_H
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#define MATCHIT_EXPRESSION_H
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#include <type_traits>
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namespace matchit {
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namespace impl {
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template <typename T>
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class Nullary : public T {
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public:
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using T::operator();
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};
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template <typename T>
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constexpr auto nullary(const T& t) {
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return Nullary<T> { t };
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}
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template <typename T>
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class Id;
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template <typename T>
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constexpr auto expr(Id<T>& id) {
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return nullary([&] { return *id; });
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}
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template <typename T>
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constexpr auto expr(const T& v) {
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return nullary([&] { return v; });
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}
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template <typename T>
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constexpr auto toNullary(T&& v) {
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if constexpr (std::is_invocable_v<std::decay_t<T>>) {
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return v;
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} else {
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return expr(v);
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}
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}
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// for constant
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template <typename T>
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class EvalTraits {
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public:
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template <typename... Args>
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constexpr static decltype(auto) evalImpl(const T& v, const Args&...) {
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return v;
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}
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};
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template <typename T>
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class EvalTraits<Nullary<T>> {
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public:
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constexpr static decltype(auto) evalImpl(const Nullary<T>& e) {
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return e();
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}
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};
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// Only allowed in nullary
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template <typename T>
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class EvalTraits<Id<T>> {
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public:
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constexpr static decltype(auto) evalImpl(const Id<T>& id) {
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return *const_cast<Id<T>&>(id);
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}
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};
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template <typename Pred>
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class Meet;
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// Unary is an alias of Meet.
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template <typename T>
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using Unary = Meet<T>;
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template <typename T>
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class EvalTraits<Unary<T>> {
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public:
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template <typename Arg>
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constexpr static decltype(auto) evalImpl(const Unary<T>& e, const Arg& arg) {
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return e(arg);
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}
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};
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class Wildcard;
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template <>
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class EvalTraits<Wildcard> {
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public:
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template <typename Arg>
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constexpr static decltype(auto) evalImpl(const Wildcard&, const Arg& arg) {
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return arg;
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}
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};
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template <typename T, typename... Args>
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constexpr decltype(auto) evaluate_(const T& t, const Args&... args) {
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return EvalTraits<T>::evalImpl(t, args...);
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}
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template <typename T>
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class IsNullaryOrId : public std::false_type {};
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template <typename T>
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class IsNullaryOrId<Id<T>> : public std::true_type {};
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template <typename T>
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class IsNullaryOrId<Nullary<T>> : public std::true_type {};
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template <typename T>
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constexpr auto isNullaryOrIdV = IsNullaryOrId<std::decay_t<T>>::value;
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#define UN_OP_FOR_NULLARY(op) \
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template <typename T, std::enable_if_t<isNullaryOrIdV<T>, bool> = true> \
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constexpr auto operator op(T const& t) { \
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return nullary([&] { return op evaluate_(t); }); \
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}
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#define BIN_OP_FOR_NULLARY(op) \
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template <typename T, typename U, std::enable_if_t<isNullaryOrIdV<T> || isNullaryOrIdV<U>, bool> = true> \
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constexpr auto operator op(T const& t, U const& u) { \
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return nullary([&] { return evaluate_(t) op evaluate_(u); }); \
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}
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// ADL will find these operators.
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UN_OP_FOR_NULLARY(!)
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UN_OP_FOR_NULLARY(-)
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#undef UN_OP_FOR_NULLARY
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BIN_OP_FOR_NULLARY(+)
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BIN_OP_FOR_NULLARY(-)
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BIN_OP_FOR_NULLARY(*)
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BIN_OP_FOR_NULLARY(/)
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BIN_OP_FOR_NULLARY(%)
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BIN_OP_FOR_NULLARY(<)
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BIN_OP_FOR_NULLARY(<=)
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BIN_OP_FOR_NULLARY(==)
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BIN_OP_FOR_NULLARY(!=)
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BIN_OP_FOR_NULLARY(>=)
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BIN_OP_FOR_NULLARY(>)
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BIN_OP_FOR_NULLARY(||)
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BIN_OP_FOR_NULLARY(&&)
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BIN_OP_FOR_NULLARY(^)
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#undef BIN_OP_FOR_NULLARY
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// Unary
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template <typename T>
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class IsUnaryOrWildcard : public std::false_type {};
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template <>
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class IsUnaryOrWildcard<Wildcard> : public std::true_type {};
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template <typename T>
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class IsUnaryOrWildcard<Unary<T>> : public std::true_type {};
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template <typename T>
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constexpr auto isUnaryOrWildcardV = IsUnaryOrWildcard<std::decay_t<T>>::value;
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// unary is an alias of meet.
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template <typename T>
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constexpr auto unary(T&& t) {
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return meet(std::forward<T>(t));
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}
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#define UN_OP_FOR_UNARY(op) \
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template <typename T, std::enable_if_t<isUnaryOrWildcardV<T>, bool> = true> \
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constexpr auto operator op(T const& t) { \
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return unary([&](auto&& arg) constexpr { return op evaluate_(t, arg); }); \
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}
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#define BIN_OP_FOR_UNARY(op) \
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template <typename T, typename U, std::enable_if_t<isUnaryOrWildcardV<T> || isUnaryOrWildcardV<U>, bool> = true> \
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constexpr auto operator op(T const& t, U const& u) { \
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return unary([&](auto&& arg) constexpr { return evaluate_(t, arg) op evaluate_(u, arg); }); \
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}
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UN_OP_FOR_UNARY(!)
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UN_OP_FOR_UNARY(-)
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#undef UN_OP_FOR_UNARY
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BIN_OP_FOR_UNARY(+)
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BIN_OP_FOR_UNARY(-)
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BIN_OP_FOR_UNARY(*)
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BIN_OP_FOR_UNARY(/)
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BIN_OP_FOR_UNARY(%)
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BIN_OP_FOR_UNARY(<)
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BIN_OP_FOR_UNARY(<=)
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BIN_OP_FOR_UNARY(==)
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BIN_OP_FOR_UNARY(!=)
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BIN_OP_FOR_UNARY(>=)
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BIN_OP_FOR_UNARY(>)
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BIN_OP_FOR_UNARY(||)
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BIN_OP_FOR_UNARY(&&)
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BIN_OP_FOR_UNARY(^)
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#undef BIN_OP_FOR_UNARY
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} // namespace impl
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using impl::expr;
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} // namespace matchit
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#endif // MATCHIT_EXPRESSION_H
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#ifndef MATCHIT_PATTERNS_H
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#define MATCHIT_PATTERNS_H
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#include <array>
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#include <cassert>
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#include <functional>
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#include <stdexcept>
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#include <variant>
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#if !defined(NO_SCALAR_REFERENCES_USED_IN_PATTERNS)
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#define NO_SCALAR_REFERENCES_USED_IN_PATTERNS 0
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#endif // !defined(NO_SCALAR_REFERENCES_USED_IN_PATTERNS)
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namespace matchit {
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namespace impl {
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template <typename I, typename S = I>
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class Subrange {
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I mBegin;
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S mEnd;
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public:
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constexpr Subrange(const I begin, const S end)
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: mBegin { begin }, mEnd { end } {}
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constexpr Subrange(const Subrange& other)
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: mBegin { other.begin() }, mEnd { other.end() } {}
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Subrange& operator=(const Subrange& other) {
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mBegin = other.begin();
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mEnd = other.end();
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return *this;
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}
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size_t size() const {
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return static_cast<size_t>(std::distance(mBegin, mEnd));
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}
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auto begin() const {
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return mBegin;
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}
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auto end() const {
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return mEnd;
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}
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};
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template <typename I, typename S>
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constexpr auto makeSubrange(I begin, S end) {
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return Subrange<I, S> { begin, end };
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}
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template <typename RangeType>
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class IterUnderlyingType {
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public:
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using beginT = decltype(std::begin(std::declval<RangeType&>()));
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using endT = decltype(std::end(std::declval<RangeType&>()));
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};
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// force array iterators fallback to pointers.
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template <typename ElemT, size_t size>
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class IterUnderlyingType<std::array<ElemT, size>> {
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public:
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using beginT = decltype(&*std::begin(std::declval<std::array<ElemT, size>&>()));
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using endT = beginT;
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};
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// force array iterators fallback to pointers.
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template <typename ElemT, size_t size>
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class IterUnderlyingType<const std::array<ElemT, size>> {
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public:
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using beginT = decltype(&*std::begin(std::declval<const std::array<ElemT, size>&>()));
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using endT = beginT;
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};
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template <typename RangeType>
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using SubrangeT =
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Subrange<typename IterUnderlyingType<RangeType>::beginT, typename IterUnderlyingType<RangeType>::endT>;
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template <typename I, typename S>
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bool operator==(const Subrange<I, S>& lhs, const Subrange<I, S>& rhs) {
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using std::operator==;
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return lhs.size() == rhs.size() && std::equal(lhs.begin(), lhs.end(), rhs.begin());
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}
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template <typename K1, typename V1, typename K2, typename V2>
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auto operator==(const std::pair<K1, V1>& t, const std::pair<K2, V2>& u) {
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return t.first == u.first && t.second == u.second;
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}
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template <typename T, typename... Ts>
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class WithinTypes {
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public:
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constexpr static auto value = (std::is_same_v<T, Ts> || ...);
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};
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template <typename T, typename Tuple>
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class PrependUnique;
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template <typename T, typename... Ts>
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class PrependUnique<T, std::tuple<Ts...>> {
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constexpr static auto unique = !WithinTypes<T, Ts...>::value;
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public:
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using type = std::conditional_t<unique, std::tuple<T, Ts...>, std::tuple<Ts...>>;
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};
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template <typename T, typename Tuple>
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using PrependUniqueT = typename PrependUnique<T, Tuple>::type;
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template <typename Tuple>
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class Unique;
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template <typename... Ts>
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using UniqueT = typename Unique<std::tuple<Ts...>>::type;
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template <>
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class Unique<std::tuple<>> {
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public:
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using type = std::tuple<>;
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};
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template <typename T, typename... Ts>
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class Unique<std::tuple<T, Ts...>> {
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public:
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using type = PrependUniqueT<T, UniqueT<Ts...>>;
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};
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static_assert(std::is_same_v<std::tuple<int32_t>, UniqueT<int32_t, int32_t>>);
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static_assert(std::is_same_v<std::tuple<std::tuple<>, int32_t>, UniqueT<int32_t, std::tuple<>, int32_t>>);
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using std::get;
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namespace detail {
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template <std::size_t start, class Tuple, std::size_t... I>
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constexpr decltype(auto) subtupleImpl(Tuple&& t, std::index_sequence<I...>) {
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return std::forward_as_tuple(get<start + I>(std::forward<Tuple>(t))...);
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}
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} // namespace detail
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// [start, end)
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template <std::size_t start, std::size_t end, class Tuple>
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constexpr decltype(auto) subtuple(Tuple&& t) {
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constexpr auto tupleSize = std::tuple_size_v<std::remove_reference_t<Tuple>>;
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static_assert(start <= end);
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static_assert(end <= tupleSize);
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return detail::subtupleImpl<start>(std::forward<Tuple>(t), std::make_index_sequence<end - start> {});
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}
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template <std::size_t start, class Tuple>
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constexpr decltype(auto) drop(Tuple&& t) {
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constexpr auto tupleSize = std::tuple_size_v<std::remove_reference_t<Tuple>>;
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static_assert(start <= tupleSize);
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return subtuple<start, tupleSize>(std::forward<Tuple>(t));
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}
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template <std::size_t len, class Tuple>
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constexpr decltype(auto) take(Tuple&& t) {
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constexpr auto tupleSize = std::tuple_size_v<std::remove_reference_t<Tuple>>;
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static_assert(len <= tupleSize);
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return subtuple<0, len>(std::forward<Tuple>(t));
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}
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template <class F, class Tuple>
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constexpr decltype(auto) apply_(F&& f, Tuple&& t) {
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return std::apply(std::forward<F>(f), drop<0>(std::forward<Tuple>(t)));
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}
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// as constexpr
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template <class F, class... Args>
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constexpr std::invoke_result_t<F, Args...>
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invoke_(F&& f, Args&&... args) noexcept(std::is_nothrow_invocable_v<F, Args...>) {
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return std::apply(std::forward<F>(f), std::forward_as_tuple(std::forward<Args>(args)...));
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}
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template <class T>
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struct decayArray {
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private:
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typedef std::remove_reference_t<T> U;
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public:
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using type = std::conditional_t<std::is_array_v<U>, std::remove_extent_t<U>*, T>;
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};
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template <class T>
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using decayArrayT = typename decayArray<T>::type;
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static_assert(std::is_same_v<decayArrayT<int32_t[]>, int32_t*>);
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static_assert(std::is_same_v<decayArrayT<const int32_t[]>, const int32_t*>);
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static_assert(std::is_same_v<decayArrayT<const int32_t&>, const int32_t&>);
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template <typename T>
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struct AddConstToPointer {
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using type =
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std::conditional_t<!std::is_pointer_v<T>, T, std::add_pointer_t<std::add_const_t<std::remove_pointer_t<T>>>>;
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};
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template <typename T>
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using AddConstToPointerT = typename AddConstToPointer<T>::type;
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static_assert(std::is_same_v<AddConstToPointerT<void*>, const void*>);
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static_assert(std::is_same_v<AddConstToPointerT<int32_t>, int32_t>);
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template <typename Pattern>
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using InternalPatternT = std::remove_reference_t<AddConstToPointerT<decayArrayT<Pattern>>>;
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template <typename Pattern>
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class PatternTraits;
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template <typename... PatternPairs>
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class PatternPairsRetType {
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public:
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using RetType = std::common_type_t<typename PatternPairs::RetType...>;
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};
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enum class IdProcess : int32_t { kCANCEL,
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kCONFIRM };
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template <typename Pattern>
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constexpr void processId(const Pattern& pattern, int32_t depth, IdProcess idProcess) {
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PatternTraits<Pattern>::processIdImpl(pattern, depth, idProcess);
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}
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template <typename Tuple>
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class Variant;
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template <typename T, typename... Ts>
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class Variant<std::tuple<T, Ts...>> {
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public:
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using type = std::variant<std::monostate, T, Ts...>;
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};
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template <typename... Ts>
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using UniqVariant = typename Variant<UniqueT<Ts...>>::type;
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template <typename... Ts>
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class Context {
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using ElementT = UniqVariant<Ts...>;
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using ContainerT = std::array<ElementT, sizeof...(Ts)>;
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ContainerT mMemHolder;
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size_t mSize = 0;
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public:
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template <typename T>
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constexpr void emplace_back(T&& t) {
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mMemHolder[mSize] = std::forward<T>(t);
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++mSize;
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}
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constexpr auto back() -> ElementT& {
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return mMemHolder[mSize - 1];
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}
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};
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template <>
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class Context<> {};
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template <typename T>
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class ContextTrait;
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template <typename... Ts>
|
|
class ContextTrait<std::tuple<Ts...>> {
|
|
public:
|
|
using ContextT = Context<Ts...>;
|
|
};
|
|
|
|
template <typename Value, typename Pattern, typename ConctextT>
|
|
constexpr auto matchPattern(Value&& value, const Pattern& pattern, int32_t depth, ConctextT& context) {
|
|
const auto result = PatternTraits<Pattern>::matchPatternImpl(std::forward<Value>(value), pattern, depth, context);
|
|
const auto process = result ? IdProcess::kCONFIRM : IdProcess::kCANCEL;
|
|
processId(pattern, depth, process);
|
|
return result;
|
|
}
|
|
|
|
template <typename Pattern, typename Func>
|
|
class PatternPair {
|
|
public:
|
|
using RetType = std::invoke_result_t<Func>;
|
|
using PatternT = Pattern;
|
|
|
|
constexpr PatternPair(const Pattern& pattern, const Func& func)
|
|
: mPattern { pattern }, mHandler { func } {}
|
|
template <typename Value, typename ContextT>
|
|
constexpr bool matchValue(Value&& value, ContextT& context) const {
|
|
return matchPattern(std::forward<Value>(value), mPattern, /*depth*/ 0, context);
|
|
}
|
|
constexpr auto execute() const {
|
|
return mHandler();
|
|
}
|
|
|
|
private:
|
|
const Pattern mPattern;
|
|
std::conditional_t<std::is_function_v<Func>, const Func&, const Func> mHandler;
|
|
};
|
|
|
|
template <typename Pattern, typename Pred>
|
|
class PostCheck;
|
|
|
|
template <typename Pred>
|
|
class When {
|
|
public:
|
|
Pred mPred;
|
|
};
|
|
|
|
template <typename Pred>
|
|
constexpr auto when(Pred&& pred) {
|
|
auto p = toNullary(pred);
|
|
return When<decltype(p)> { p };
|
|
}
|
|
|
|
template <typename Pattern>
|
|
class PatternHelper {
|
|
public:
|
|
constexpr explicit PatternHelper(const Pattern& pattern)
|
|
: mPattern { pattern } {}
|
|
template <typename Func>
|
|
constexpr auto operator=(Func&& func) {
|
|
auto f = toNullary(func);
|
|
return PatternPair<Pattern, decltype(f)> { mPattern, f };
|
|
}
|
|
template <typename Pred>
|
|
constexpr auto operator|(const When<Pred>& w) {
|
|
return PatternHelper<PostCheck<Pattern, Pred>>(PostCheck(mPattern, w.mPred));
|
|
}
|
|
|
|
private:
|
|
const Pattern mPattern;
|
|
};
|
|
|
|
template <typename... Patterns>
|
|
class Ds;
|
|
|
|
template <typename... Patterns>
|
|
constexpr auto ds(const Patterns&... patterns) -> Ds<Patterns...>;
|
|
|
|
template <typename Pattern>
|
|
class OooBinder;
|
|
|
|
class PatternPipable {
|
|
public:
|
|
template <typename Pattern>
|
|
// ReSharper disable once CppDFAUnreachableFunctionCall
|
|
constexpr auto operator|(const Pattern& p) const {
|
|
return PatternHelper<Pattern> { p };
|
|
}
|
|
|
|
template <typename T>
|
|
constexpr auto operator|(const T* p) const {
|
|
return PatternHelper<const T*> { p };
|
|
}
|
|
|
|
template <typename Pattern>
|
|
constexpr auto operator|(const OooBinder<Pattern>& p) const {
|
|
return operator|(ds(p));
|
|
}
|
|
};
|
|
|
|
constexpr PatternPipable is {};
|
|
|
|
template <typename Pattern>
|
|
class PatternTraits {
|
|
public:
|
|
template <typename Value>
|
|
using AppResultTuple = std::tuple<>;
|
|
|
|
constexpr static auto nbIdV = 0;
|
|
|
|
template <typename Value, typename ContextT>
|
|
constexpr static auto
|
|
matchPatternImpl(Value&& value, const Pattern& pattern, int32_t /* depth */, ContextT& /*context*/) {
|
|
return pattern == std::forward<Value>(value);
|
|
}
|
|
constexpr static void processIdImpl(const Pattern&, int32_t /*depth*/, IdProcess) {}
|
|
};
|
|
|
|
class Wildcard {};
|
|
|
|
constexpr Wildcard _;
|
|
|
|
template <>
|
|
class PatternTraits<Wildcard> {
|
|
using Pattern = Wildcard;
|
|
|
|
public:
|
|
template <typename Value>
|
|
using AppResultTuple = std::tuple<>;
|
|
|
|
constexpr static auto nbIdV = 0;
|
|
|
|
template <typename Value, typename ContextT>
|
|
constexpr static bool matchPatternImpl(Value&&, const Pattern&, int32_t, ContextT&) {
|
|
return true;
|
|
}
|
|
constexpr static void processIdImpl(const Pattern&, int32_t /*depth*/, IdProcess) {}
|
|
};
|
|
|
|
template <typename... Patterns>
|
|
class Or {
|
|
public:
|
|
constexpr explicit Or(const Patterns&... patterns)
|
|
: mPatterns { patterns... } {}
|
|
constexpr const auto& patterns() const {
|
|
return mPatterns;
|
|
}
|
|
|
|
private:
|
|
std::tuple<InternalPatternT<Patterns>...> mPatterns;
|
|
};
|
|
|
|
template <typename... Patterns>
|
|
constexpr auto or_(const Patterns&... patterns) {
|
|
return Or<Patterns...> { patterns... };
|
|
}
|
|
|
|
template <typename... Patterns>
|
|
class PatternTraits<Or<Patterns...>> {
|
|
public:
|
|
template <typename Value>
|
|
using AppResultTuple =
|
|
decltype(std::tuple_cat(typename PatternTraits<Patterns>::template AppResultTuple<Value> {}...));
|
|
|
|
constexpr static auto nbIdV = (PatternTraits<Patterns>::nbIdV + ... + 0);
|
|
|
|
template <typename Value, typename ContextT>
|
|
constexpr static auto
|
|
matchPatternImpl(Value&& value, const Or<Patterns...>& orPat, int32_t depth, ContextT& context) {
|
|
constexpr auto patSize = sizeof...(Patterns);
|
|
return std::apply(
|
|
[&value, depth, &context](const auto&... patterns) {
|
|
return (matchPattern(value, patterns, depth + 1, context) || ...);
|
|
},
|
|
take<patSize - 1>(orPat.patterns())
|
|
) ||
|
|
matchPattern(std::forward<Value>(value), get<patSize - 1>(orPat.patterns()), depth + 1, context);
|
|
}
|
|
constexpr static void processIdImpl(const Or<Patterns...>& orPat, int32_t depth, IdProcess idProcess) {
|
|
return std::apply(
|
|
[depth, idProcess](const Patterns&... patterns) { return (processId(patterns, depth, idProcess), ...); },
|
|
orPat.patterns()
|
|
);
|
|
}
|
|
};
|
|
|
|
template <typename Pred>
|
|
class Meet : public Pred {
|
|
public:
|
|
using Pred::operator();
|
|
};
|
|
|
|
template <typename Pred>
|
|
constexpr auto meet(const Pred& pred) {
|
|
return Meet<Pred> { pred };
|
|
}
|
|
|
|
template <typename Pred>
|
|
class PatternTraits<Meet<Pred>> {
|
|
public:
|
|
template <typename Value>
|
|
using AppResultTuple = std::tuple<>;
|
|
|
|
constexpr static auto nbIdV = 0;
|
|
|
|
template <typename Value, typename ContextT>
|
|
constexpr static auto matchPatternImpl(Value&& value, const Meet<Pred>& meetPat, int32_t /* depth */, ContextT&) {
|
|
return meetPat(std::forward<Value>(value));
|
|
}
|
|
constexpr static void processIdImpl(const Meet<Pred>&, int32_t /*depth*/, IdProcess) {}
|
|
};
|
|
|
|
template <typename Unary, typename Pattern>
|
|
class App {
|
|
public:
|
|
constexpr App(Unary&& unary, const Pattern& pattern)
|
|
: mUnary { std::forward<Unary>(unary) }, mPattern { pattern } {}
|
|
constexpr const auto& unary() const {
|
|
return mUnary;
|
|
}
|
|
constexpr const auto& pattern() const {
|
|
return mPattern;
|
|
}
|
|
|
|
private:
|
|
const Unary mUnary;
|
|
const InternalPatternT<Pattern> mPattern;
|
|
};
|
|
|
|
template <typename Unary, typename Pattern>
|
|
constexpr auto app(Unary&& unary, const Pattern& pattern) {
|
|
return App<Unary, Pattern> { std::forward<Unary>(unary), pattern };
|
|
}
|
|
|
|
constexpr auto y = 1;
|
|
static_assert(std::holds_alternative<const int32_t*>(std::variant<std::monostate, const int32_t*> { &y }));
|
|
|
|
template <typename Unary, typename Pattern>
|
|
class PatternTraits<App<Unary, Pattern>> {
|
|
public:
|
|
template <typename Value>
|
|
using AppResult = std::invoke_result_t<Unary, Value>;
|
|
// We store value for scalar types in Id and they can not be moved. So to
|
|
// support constexpr.
|
|
template <typename Value>
|
|
using AppResultCurTuple = std::conditional_t<
|
|
std::is_lvalue_reference_v<AppResult<Value>>
|
|
#if NO_SCALAR_REFERENCES_USED_IN_PATTERNS
|
|
|| std::is_scalar_v<AppResult<Value>>
|
|
#endif // NO_SCALAR_REFERENCES_USED_IN_PATTERNS
|
|
,
|
|
std::tuple<>,
|
|
std::tuple<std::decay_t<AppResult<Value>>>>;
|
|
|
|
template <typename Value>
|
|
using AppResultTuple = decltype(std::tuple_cat(
|
|
std::declval<AppResultCurTuple<Value>>(),
|
|
std::declval<typename PatternTraits<Pattern>::template AppResultTuple<AppResult<Value>>>()
|
|
));
|
|
|
|
constexpr static auto nbIdV = PatternTraits<Pattern>::nbIdV;
|
|
|
|
template <typename Value, typename ContextT>
|
|
constexpr static auto
|
|
matchPatternImpl(Value&& value, const App<Unary, Pattern>& appPat, const int32_t depth, ContextT& context) {
|
|
if constexpr (std::is_same_v<AppResultCurTuple<Value>, std::tuple<>>) {
|
|
return matchPattern(
|
|
std::forward<AppResult<Value>>(invoke_(appPat.unary(), value)), appPat.pattern(), depth + 1, context
|
|
);
|
|
} else {
|
|
context.emplace_back(invoke_(appPat.unary(), value));
|
|
decltype(auto) result = get<std::decay_t<AppResult<Value>>>(context.back());
|
|
return matchPattern(std::forward<AppResult<Value>>(result), appPat.pattern(), depth + 1, context);
|
|
}
|
|
}
|
|
constexpr static void processIdImpl(const App<Unary, Pattern>& appPat, int32_t depth, IdProcess idProcess) {
|
|
return processId(appPat.pattern(), depth, idProcess);
|
|
}
|
|
};
|
|
|
|
template <typename... Patterns>
|
|
class And {
|
|
public:
|
|
constexpr explicit And(const Patterns&... patterns)
|
|
: mPatterns { patterns... } {}
|
|
constexpr const auto& patterns() const {
|
|
return mPatterns;
|
|
}
|
|
|
|
private:
|
|
std::tuple<InternalPatternT<Patterns>...> mPatterns;
|
|
};
|
|
|
|
template <typename... Patterns>
|
|
constexpr auto and_(const Patterns&... patterns) {
|
|
return And<Patterns...> { patterns... };
|
|
}
|
|
|
|
template <typename Tuple>
|
|
class NbIdInTuple;
|
|
|
|
template <typename... Patterns>
|
|
class NbIdInTuple<std::tuple<Patterns...>> {
|
|
public:
|
|
constexpr static auto nbIdV = (PatternTraits<std::decay_t<Patterns>>::nbIdV + ... + 0);
|
|
};
|
|
|
|
template <typename... Patterns>
|
|
class PatternTraits<And<Patterns...>> {
|
|
public:
|
|
template <typename Value>
|
|
using AppResultTuple =
|
|
decltype(std::tuple_cat(std::declval<typename PatternTraits<Patterns>::template AppResultTuple<Value>>()...));
|
|
|
|
constexpr static auto nbIdV = (PatternTraits<Patterns>::nbIdV + ... + 0);
|
|
|
|
template <typename Value, typename ContextT>
|
|
constexpr static auto
|
|
matchPatternImpl(Value&& value, const And<Patterns...>& andPat, int32_t depth, ContextT& context) {
|
|
constexpr auto patSize = sizeof...(Patterns);
|
|
const auto exceptLast = std::apply(
|
|
[&value, depth, &context](const auto&... patterns) {
|
|
return (matchPattern(value, patterns, depth + 1, context) && ...);
|
|
},
|
|
take<patSize - 1>(andPat.patterns())
|
|
);
|
|
|
|
// No Id in patterns except the last one.
|
|
if constexpr (NbIdInTuple<std::decay_t<decltype(take<patSize - 1>(andPat.patterns()))>>::nbIdV == 0) {
|
|
return exceptLast &&
|
|
matchPattern(std::forward<Value>(value), get<patSize - 1>(andPat.patterns()), depth + 1, context);
|
|
} else {
|
|
return exceptLast && matchPattern(value, get<patSize - 1>(andPat.patterns()), depth + 1, context);
|
|
}
|
|
}
|
|
constexpr static void processIdImpl(const And<Patterns...>& andPat, int32_t depth, IdProcess idProcess) {
|
|
return std::apply(
|
|
[depth, idProcess](const Patterns&... patterns) { return (processId(patterns, depth, idProcess), ...); },
|
|
andPat.patterns()
|
|
);
|
|
}
|
|
};
|
|
|
|
template <typename Pattern>
|
|
class Not {
|
|
public:
|
|
explicit Not(const Pattern& pattern)
|
|
: mPattern { pattern } {}
|
|
const auto& pattern() const {
|
|
return mPattern;
|
|
}
|
|
|
|
private:
|
|
InternalPatternT<Pattern> mPattern;
|
|
};
|
|
|
|
template <typename Pattern>
|
|
constexpr auto not_(const Pattern& pattern) {
|
|
return Not<Pattern> { pattern };
|
|
}
|
|
|
|
template <typename Pattern>
|
|
class PatternTraits<Not<Pattern>> {
|
|
public:
|
|
template <typename Value>
|
|
using AppResultTuple = typename PatternTraits<Pattern>::template AppResultTuple<Value>;
|
|
|
|
constexpr static auto nbIdV = PatternTraits<Pattern>::nbIdV;
|
|
|
|
template <typename Value, typename ContextT>
|
|
constexpr static auto
|
|
matchPatternImpl(Value&& value, const Not<Pattern>& notPat, const int32_t depth, ContextT& context) {
|
|
return !matchPattern(std::forward<Value>(value), notPat.pattern(), depth + 1, context);
|
|
}
|
|
constexpr static void processIdImpl(const Not<Pattern>& notPat, int32_t depth, IdProcess idProcess) {
|
|
processId(notPat.pattern(), depth, idProcess);
|
|
}
|
|
};
|
|
|
|
template <typename Ptr, typename Value, typename = std::void_t<>>
|
|
struct StorePointer : std::false_type {};
|
|
|
|
template <typename Type>
|
|
using ValueVariant = std::conditional_t<
|
|
std::is_lvalue_reference_v<Type>,
|
|
UniqVariant<std::remove_reference_t<Type>*>,
|
|
std::conditional_t<
|
|
std::is_rvalue_reference_v<Type>,
|
|
UniqVariant<std::remove_reference_t<Type>, std::remove_reference_t<Type>*>,
|
|
std::conditional_t<
|
|
std::is_abstract_v<std::remove_reference_t<Type>>,
|
|
UniqVariant<std::remove_reference_t<Type>*, const std::remove_reference_t<Type>*>,
|
|
UniqVariant<
|
|
std::remove_reference_t<Type>,
|
|
std::remove_reference_t<Type>*,
|
|
const std::remove_reference_t<Type>*>>>>;
|
|
|
|
template <typename Type, typename Value>
|
|
struct StorePointer<
|
|
Type,
|
|
Value,
|
|
std::void_t<decltype(std::declval<ValueVariant<Type>&>() = &std::declval<Value>())>>
|
|
: std::is_reference<Value> // need to double check this condition. to loosen it.
|
|
{};
|
|
|
|
static_assert(!StorePointer<char, char>::value);
|
|
static_assert(StorePointer<char, char&>::value);
|
|
static_assert(StorePointer<const char, const char&>::value);
|
|
static_assert(StorePointer<const char, char&>::value);
|
|
static_assert(StorePointer<const std::tuple<int32_t&, int32_t&>, const std::tuple<int32_t&, int32_t&>&>::value);
|
|
|
|
template <typename... Ts>
|
|
class Overload : public Ts... {
|
|
public:
|
|
using Ts::operator()...;
|
|
};
|
|
|
|
template <typename... Ts>
|
|
constexpr auto overload(Ts&&... ts) {
|
|
return Overload<Ts...> { ts... };
|
|
}
|
|
|
|
template <typename Pattern>
|
|
class OooBinder;
|
|
|
|
class Ooo;
|
|
|
|
template <typename Type>
|
|
class IdTraits {
|
|
public:
|
|
constexpr static auto
|
|
#if defined(__has_feature)
|
|
#if __has_feature(address_sanitizer)
|
|
__attribute__((no_sanitize_address))
|
|
#endif
|
|
#endif
|
|
equal(Type const& lhs, Type const& rhs) {
|
|
return lhs == rhs;
|
|
}
|
|
};
|
|
|
|
template <typename Type>
|
|
class IdBlockBase {
|
|
int32_t mDepth;
|
|
|
|
protected:
|
|
ValueVariant<Type> mVariant;
|
|
|
|
public:
|
|
constexpr IdBlockBase()
|
|
: mDepth {}, mVariant {} {}
|
|
|
|
constexpr auto& variant() {
|
|
return mVariant;
|
|
}
|
|
constexpr void reset(const int32_t depth) {
|
|
if (mDepth - depth >= 0) {
|
|
mVariant = {};
|
|
mDepth = depth;
|
|
}
|
|
}
|
|
constexpr void confirm(const int32_t depth) {
|
|
if (mDepth > depth || mDepth == 0) {
|
|
assert(depth == mDepth - 1 || depth == mDepth || mDepth == 0);
|
|
mDepth = depth;
|
|
}
|
|
}
|
|
};
|
|
|
|
constexpr IdBlockBase<int> dummy;
|
|
|
|
template <typename Type>
|
|
class IdBlock : public IdBlockBase<Type> {
|
|
public:
|
|
constexpr auto hasValue() const {
|
|
return std::visit(
|
|
overload(
|
|
[](const Type&) { return true; },
|
|
[](const Type*) { return true; },
|
|
// [](Type *)
|
|
// { return true; },
|
|
[](const std::monostate&) { return false; }
|
|
),
|
|
IdBlockBase<Type>::mVariant
|
|
);
|
|
}
|
|
constexpr decltype(auto) get() const {
|
|
return std::visit(
|
|
overload(
|
|
[](const Type& v) -> const Type& { return v; },
|
|
[](const Type* p) -> const Type& { return *p; },
|
|
[](Type* p) -> const Type& { return *p; },
|
|
[](const std::monostate&) -> const Type& { throw std::logic_error("invalid state!"); }
|
|
),
|
|
IdBlockBase<Type>::mVariant
|
|
);
|
|
}
|
|
};
|
|
|
|
template <typename Type>
|
|
class IdBlock<const Type&> : public IdBlock<Type> {};
|
|
|
|
template <typename Type>
|
|
class IdBlock<Type&> : public IdBlockBase<Type&> {
|
|
public:
|
|
constexpr auto hasValue() const {
|
|
return std::visit(
|
|
overload([](Type*) { return true; }, [](const std::monostate&) { return false; }),
|
|
IdBlockBase<Type&>::mVariant
|
|
);
|
|
}
|
|
|
|
constexpr decltype(auto) get() {
|
|
return std::visit(
|
|
overload(
|
|
[](Type* v) -> Type& {
|
|
if (v == nullptr) {
|
|
throw std::logic_error("Trying to dereference a nullptr!");
|
|
}
|
|
return *v;
|
|
},
|
|
[](std::monostate&) -> Type& { throw std::logic_error("Invalid state!"); }
|
|
),
|
|
IdBlockBase<Type&>::mVariant
|
|
);
|
|
}
|
|
};
|
|
|
|
template <typename Type>
|
|
class IdBlock<Type&&> : public IdBlockBase<Type&&> {
|
|
public:
|
|
constexpr auto hasValue() const {
|
|
return std::visit(
|
|
overload(
|
|
[](const Type&) { return true; }, [](Type*) { return true; }, [](const std::monostate&) { return false; }
|
|
),
|
|
IdBlockBase<Type&&>::mVariant
|
|
);
|
|
}
|
|
|
|
constexpr decltype(auto) get() {
|
|
return std::visit(
|
|
overload(
|
|
[](Type& v) -> Type& { return v; },
|
|
[](Type* v) -> Type& {
|
|
if (v == nullptr) {
|
|
throw std::logic_error("Trying to dereference a nullptr!");
|
|
}
|
|
return *v;
|
|
},
|
|
[](std::monostate&) -> Type& { throw std::logic_error("Invalid state!"); }
|
|
),
|
|
IdBlockBase<Type&&>::mVariant
|
|
);
|
|
}
|
|
};
|
|
|
|
template <typename Type>
|
|
class IdUtil {
|
|
public:
|
|
template <typename Value>
|
|
constexpr static auto bindValue(ValueVariant<Type>& v, Value&& value, std::false_type /* StorePointer */) {
|
|
// for constexpr
|
|
v = ValueVariant<Type> { std::forward<Value>(value) };
|
|
}
|
|
template <typename Value>
|
|
constexpr static auto bindValue(ValueVariant<Type>& v, Value&& value, std::true_type /* StorePointer */) {
|
|
v = ValueVariant<Type> { &value };
|
|
}
|
|
};
|
|
|
|
template <typename Type>
|
|
class Id {
|
|
private:
|
|
using BlockT = IdBlock<Type>;
|
|
using BlockVT = std::variant<BlockT, BlockT*>;
|
|
BlockVT mBlock = BlockT {};
|
|
|
|
constexpr decltype(auto) internalValue() const {
|
|
return block().get();
|
|
}
|
|
|
|
public:
|
|
constexpr Id() = default;
|
|
|
|
constexpr Id(const Id& id) {
|
|
mBlock = BlockVT { &id.block() };
|
|
}
|
|
|
|
// non-const to inform users not to mark Id as const.
|
|
template <typename Pattern>
|
|
constexpr auto at(Pattern&& pattern) {
|
|
return and_(pattern, *this);
|
|
}
|
|
|
|
// non-const to inform users not to mark Id as const.
|
|
constexpr auto at(const Ooo&) {
|
|
return OooBinder<Type> { *this };
|
|
}
|
|
|
|
constexpr BlockT& block() const {
|
|
return std::visit(
|
|
overload([](BlockT& v) -> BlockT& { return v; }, [](BlockT* p) -> BlockT& { return *p; }),
|
|
// constexpr does not allow mutable, we use const_cast
|
|
// instead. Never declare Id as const.
|
|
const_cast<BlockVT&>(mBlock)
|
|
);
|
|
}
|
|
|
|
template <typename Value>
|
|
constexpr auto matchValue(Value&& v) const {
|
|
if (hasValue()) {
|
|
return IdTraits<std::decay_t<Type>>::equal(internalValue(), v);
|
|
}
|
|
IdUtil<Type>::bindValue(block().variant(), std::forward<Value>(v), StorePointer<Type, Value> {});
|
|
return true;
|
|
}
|
|
constexpr void reset(int32_t depth) const {
|
|
return block().reset(depth);
|
|
}
|
|
constexpr void confirm(int32_t depth) const {
|
|
return block().confirm(depth);
|
|
}
|
|
constexpr bool hasValue() const {
|
|
return block().hasValue();
|
|
}
|
|
// non-const to inform users not to mark Id as const.
|
|
constexpr decltype(auto) get() {
|
|
return block().get();
|
|
}
|
|
// non-const to inform users not to mark Id as const.
|
|
constexpr decltype(auto) operator*() {
|
|
return get();
|
|
}
|
|
};
|
|
|
|
template <typename Type>
|
|
class PatternTraits<Id<Type>> {
|
|
public:
|
|
template <typename Value>
|
|
using AppResultTuple = std::tuple<>;
|
|
|
|
constexpr static auto nbIdV = true;
|
|
|
|
template <typename Value, typename ContextT>
|
|
constexpr static auto matchPatternImpl(Value&& value, const Id<Type>& idPat, int32_t /* depth */, ContextT&) {
|
|
return idPat.matchValue(std::forward<Value>(value));
|
|
}
|
|
constexpr static void processIdImpl(const Id<Type>& idPat, int32_t depth, const IdProcess idProcess) {
|
|
switch (idProcess) {
|
|
case IdProcess::kCANCEL: idPat.reset(depth); break;
|
|
|
|
case IdProcess::kCONFIRM: idPat.confirm(depth); break;
|
|
}
|
|
}
|
|
};
|
|
|
|
template <typename... Patterns>
|
|
class Ds {
|
|
public:
|
|
constexpr explicit Ds(const Patterns&... patterns)
|
|
: mPatterns { patterns... } {}
|
|
constexpr const auto& patterns() const {
|
|
return mPatterns;
|
|
}
|
|
|
|
using Type = std::tuple<InternalPatternT<Patterns>...>;
|
|
|
|
private:
|
|
Type mPatterns;
|
|
};
|
|
|
|
template <typename... Patterns>
|
|
constexpr auto ds(const Patterns&... patterns) -> Ds<Patterns...> {
|
|
return Ds<Patterns...> { patterns... };
|
|
}
|
|
|
|
template <typename T>
|
|
class OooBinder {
|
|
Id<T> mId;
|
|
|
|
public:
|
|
explicit OooBinder(const Id<T>& id)
|
|
: mId { id } {}
|
|
decltype(auto) binder() const {
|
|
return mId;
|
|
}
|
|
};
|
|
|
|
class Ooo {
|
|
public:
|
|
template <typename T>
|
|
constexpr auto operator()(Id<T> id) const {
|
|
return OooBinder<T> { id };
|
|
}
|
|
};
|
|
|
|
constexpr Ooo ooo;
|
|
|
|
template <>
|
|
class PatternTraits<Ooo> {
|
|
public:
|
|
template <typename Value>
|
|
using AppResultTuple = std::tuple<>;
|
|
|
|
constexpr static auto nbIdV = false;
|
|
|
|
template <typename Value, typename ContextT>
|
|
constexpr static auto matchPatternImpl(Value&&, Ooo, int32_t /*depth*/, ContextT&) {
|
|
return true;
|
|
}
|
|
constexpr static void processIdImpl(Ooo, int32_t /*depth*/, IdProcess) {}
|
|
};
|
|
|
|
template <typename Pattern>
|
|
class PatternTraits<OooBinder<Pattern>> {
|
|
public:
|
|
template <typename Value>
|
|
using AppResultTuple = typename PatternTraits<Pattern>::template AppResultTuple<Value>;
|
|
|
|
constexpr static auto nbIdV = PatternTraits<Pattern>::nbIdV;
|
|
|
|
template <typename Value, typename ContextT>
|
|
constexpr static auto
|
|
matchPatternImpl(Value&& value, const OooBinder<Pattern>& oooBinderPat, const int32_t depth, ContextT& context) {
|
|
return matchPattern(std::forward<Value>(value), oooBinderPat.binder(), depth + 1, context);
|
|
}
|
|
constexpr static void processIdImpl(const OooBinder<Pattern>& oooBinderPat, int32_t depth, IdProcess idProcess) {
|
|
processId(oooBinderPat.binder(), depth, idProcess);
|
|
}
|
|
};
|
|
|
|
template <typename T>
|
|
class IsOoo : public std::false_type {};
|
|
|
|
template <>
|
|
class IsOoo<Ooo> : public std::true_type {};
|
|
|
|
template <typename T>
|
|
class IsOooBinder : public std::false_type {};
|
|
|
|
template <typename T>
|
|
class IsOooBinder<OooBinder<T>> : public std::true_type {};
|
|
|
|
template <typename T>
|
|
constexpr auto isOooBinderV = IsOooBinder<std::decay_t<T>>::value;
|
|
|
|
template <typename T>
|
|
constexpr auto isOooOrBinderV = IsOoo<std::decay_t<T>>::value || isOooBinderV<T>;
|
|
|
|
template <typename... Patterns>
|
|
constexpr auto nbOooOrBinderV = ((isOooOrBinderV<Patterns> ? 1 : 0) + ... + 0);
|
|
|
|
static_assert(nbOooOrBinderV<int32_t&, const Ooo&, const char*, Wildcard, const Ooo> == 2);
|
|
|
|
template <typename Tuple, std::size_t... I>
|
|
constexpr size_t findOooIdxImpl(std::index_sequence<I...>) {
|
|
return ((isOooOrBinderV<decltype(get<I>(std::declval<Tuple>()))> ? I : 0) + ...);
|
|
}
|
|
|
|
template <typename Tuple>
|
|
constexpr size_t findOooIdx() {
|
|
return findOooIdxImpl<Tuple>(std::make_index_sequence<std::tuple_size_v<std::remove_reference_t<Tuple>>> {});
|
|
}
|
|
|
|
static_assert(isOooOrBinderV<Ooo>);
|
|
static_assert(isOooOrBinderV<OooBinder<int32_t>>);
|
|
static_assert(findOooIdx<std::tuple<int32_t, OooBinder<int32_t>, const char*>>() == 1);
|
|
static_assert(findOooIdx<std::tuple<int32_t, Ooo, const char*>>() == 1);
|
|
|
|
using std::get;
|
|
template <
|
|
std::size_t valueStartIdx,
|
|
std::size_t patternStartIdx,
|
|
std::size_t... I,
|
|
typename ValueTuple,
|
|
typename PatternTuple,
|
|
typename ContextT>
|
|
constexpr decltype(auto)
|
|
matchPatternMultipleImpl(ValueTuple&& valueTuple, PatternTuple&& patternTuple, const int32_t depth, ContextT& context, std::index_sequence<I...>) {
|
|
const auto func = [&]<typename T>(T&& value, auto&& pattern) {
|
|
return matchPattern(std::forward<T>(value), pattern, depth + 1, context);
|
|
};
|
|
static_cast<void>(func);
|
|
return (
|
|
func(
|
|
get<I + valueStartIdx>(std::forward<ValueTuple>(valueTuple)), std::get<I + patternStartIdx>(patternTuple)
|
|
) &&
|
|
...
|
|
);
|
|
}
|
|
|
|
template <
|
|
std::size_t valueStartIdx,
|
|
std::size_t patternStartIdx,
|
|
std::size_t size,
|
|
typename ValueTuple,
|
|
typename PatternTuple,
|
|
typename ContextT>
|
|
constexpr decltype(auto)
|
|
matchPatternMultiple(ValueTuple&& valueTuple, PatternTuple&& patternTuple, int32_t depth, ContextT& context) {
|
|
return matchPatternMultipleImpl<valueStartIdx, patternStartIdx>(
|
|
std::forward<ValueTuple>(valueTuple), patternTuple, depth, context, std::make_index_sequence<size> {}
|
|
);
|
|
}
|
|
|
|
template <
|
|
std::size_t patternStartIdx,
|
|
std::size_t... I,
|
|
typename RangeBegin,
|
|
typename PatternTuple,
|
|
typename ContextT>
|
|
constexpr decltype(auto)
|
|
matchPatternRangeImpl(RangeBegin&& rangeBegin, PatternTuple&& patternTuple, const int32_t depth, ContextT& context, std::index_sequence<I...>) {
|
|
const auto func = [&]<typename T>(T&& value, auto&& pattern) {
|
|
return matchPattern(std::forward<T>(value), pattern, depth + 1, context);
|
|
};
|
|
static_cast<void>(func);
|
|
// Fix Me, avoid call next from begin every time.
|
|
return (func(*std::next(rangeBegin, static_cast<long>(I)), std::get<I + patternStartIdx>(patternTuple)) && ...);
|
|
}
|
|
|
|
template <
|
|
std::size_t patternStartIdx,
|
|
std::size_t size,
|
|
typename ValueRangeBegin,
|
|
typename PatternTuple,
|
|
typename ContextT>
|
|
constexpr decltype(auto) matchPatternRange(
|
|
ValueRangeBegin&& valueRangeBegin,
|
|
PatternTuple&& patternTuple,
|
|
int32_t depth,
|
|
ContextT& context
|
|
) {
|
|
return matchPatternRangeImpl<patternStartIdx>(
|
|
valueRangeBegin, patternTuple, depth, context, std::make_index_sequence<size> {}
|
|
);
|
|
}
|
|
|
|
template <std::size_t start, typename Indices, typename Tuple>
|
|
class IndexedTypes;
|
|
|
|
template <typename Tuple, std::size_t start, std::size_t... I>
|
|
class IndexedTypes<start, std::index_sequence<I...>, Tuple> {
|
|
public:
|
|
using type = std::tuple<std::decay_t<decltype(std::get<start + I>(std::declval<Tuple>()))>...>;
|
|
};
|
|
|
|
template <std::size_t start, std::size_t end, class Tuple>
|
|
class SubTypes {
|
|
constexpr static auto tupleSize = std::tuple_size_v<std::remove_reference_t<Tuple>>;
|
|
static_assert(start <= end);
|
|
static_assert(end <= tupleSize);
|
|
|
|
using Indices = std::make_index_sequence<end - start>;
|
|
|
|
public:
|
|
using type = typename IndexedTypes<start, Indices, Tuple>::type;
|
|
};
|
|
|
|
template <std::size_t start, std::size_t end, class Tuple>
|
|
using SubTypesT = typename SubTypes<start, end, Tuple>::type;
|
|
|
|
static_assert(std::is_same_v<
|
|
std::tuple<std::nullptr_t>,
|
|
SubTypesT<3, 4, std::tuple<char, bool, int32_t, std::nullptr_t>>>);
|
|
static_assert(std::is_same_v<std::tuple<char>, SubTypesT<0, 1, std::tuple<char, bool, int32_t, std::nullptr_t>>>);
|
|
static_assert(std::is_same_v<std::tuple<>, SubTypesT<1, 1, std::tuple<char, bool, int32_t, std::nullptr_t>>>);
|
|
static_assert(std::is_same_v<
|
|
std::tuple<int32_t, std::nullptr_t>,
|
|
SubTypesT<2, 4, std::tuple<char, bool, int32_t, std::nullptr_t>>>);
|
|
|
|
template <typename ValueTuple>
|
|
class IsArray : public std::false_type {};
|
|
|
|
template <typename T, size_t s>
|
|
class IsArray<std::array<T, s>> : public std::true_type {};
|
|
|
|
template <typename ValueTuple>
|
|
constexpr auto isArrayV = IsArray<std::decay_t<ValueTuple>>::value;
|
|
|
|
template <typename Value, typename = std::void_t<>>
|
|
struct IsTupleLike : std::false_type {};
|
|
|
|
template <typename Value>
|
|
// ReSharper disable once CppUseTypeTraitAlias
|
|
struct IsTupleLike<Value, std::void_t<decltype(std::tuple_size<Value>::value)>> : std::true_type {};
|
|
|
|
template <typename ValueTuple>
|
|
constexpr auto isTupleLikeV = IsTupleLike<std::decay_t<ValueTuple>>::value;
|
|
|
|
static_assert(isTupleLikeV<std::pair<int32_t, char>>);
|
|
static_assert(!isTupleLikeV<bool>);
|
|
|
|
template <typename Value, typename = std::void_t<>>
|
|
struct IsRange : std::false_type {};
|
|
|
|
template <typename Value>
|
|
struct IsRange<
|
|
Value,
|
|
std::void_t<decltype(std::begin(std::declval<Value>())), decltype(std::end(std::declval<Value>()))>>
|
|
: std::true_type {};
|
|
|
|
template <typename ValueTuple>
|
|
constexpr auto isRangeV = IsRange<std::decay_t<ValueTuple>>::value;
|
|
|
|
static_assert(!isRangeV<std::pair<int32_t, char>>);
|
|
static_assert(isRangeV<const std::array<int32_t, 5>>);
|
|
|
|
template <typename... Patterns>
|
|
class PatternTraits<Ds<Patterns...>> {
|
|
constexpr static auto nbOooOrBinder = nbOooOrBinderV<Patterns...>;
|
|
static_assert(nbOooOrBinder == 0 || nbOooOrBinder == 1);
|
|
|
|
public:
|
|
template <typename PsTuple, typename VsTuple>
|
|
class PairPV;
|
|
|
|
template <typename... Ps, typename... Vs>
|
|
class PairPV<std::tuple<Ps...>, std::tuple<Vs...>> {
|
|
public:
|
|
using type =
|
|
decltype(std::tuple_cat(std::declval<typename PatternTraits<Ps>::template AppResultTuple<Vs>>()...));
|
|
};
|
|
|
|
template <std::size_t nbOoos, typename ValueTuple>
|
|
class AppResultForTupleHelper;
|
|
|
|
template <typename... Values>
|
|
class AppResultForTupleHelper<0, std::tuple<Values...>> {
|
|
public:
|
|
using type =
|
|
decltype(std::tuple_cat(std::declval<typename PatternTraits<Patterns>::template AppResultTuple<Values>>()...)
|
|
);
|
|
};
|
|
|
|
template <typename... Values>
|
|
class AppResultForTupleHelper<1, std::tuple<Values...>> {
|
|
constexpr static auto idxOoo = findOooIdx<typename Ds<Patterns...>::Type>();
|
|
using Ps0 = SubTypesT<0, idxOoo, std::tuple<Patterns...>>;
|
|
using Vs0 = SubTypesT<0, idxOoo, std::tuple<Values...>>;
|
|
constexpr static auto isBinder = isOooBinderV<std::tuple_element_t<idxOoo, std::tuple<Patterns...>>>;
|
|
// <0, ...int32_t> to workaround compile failure for std::tuple<>.
|
|
using ElemT = std::tuple_element_t<0, std::tuple<std::remove_reference_t<Values>..., int32_t>>;
|
|
constexpr static int64_t diff = static_cast<int64_t>(sizeof...(Values) - sizeof...(Patterns));
|
|
constexpr static size_t clippedDiff = static_cast<size_t>(diff > 0 ? diff : 0);
|
|
using OooResultTuple =
|
|
std::conditional_t<isBinder, std::tuple<SubrangeT<std::array<ElemT, clippedDiff>>>, std::tuple<>>;
|
|
using FirstHalfTuple = typename PairPV<Ps0, Vs0>::type;
|
|
using Ps1 = SubTypesT<idxOoo + 1, sizeof...(Patterns), std::tuple<Patterns...>>;
|
|
constexpr static auto vs1Start = static_cast<size_t>(static_cast<int64_t>(idxOoo) + 1 + diff);
|
|
using Vs1 = SubTypesT<vs1Start, sizeof...(Values), std::tuple<Values...>>;
|
|
using SecondHalfTuple = typename PairPV<Ps1, Vs1>::type;
|
|
|
|
public:
|
|
using type = decltype(std::tuple_cat(
|
|
std::declval<FirstHalfTuple>(),
|
|
std::declval<OooResultTuple>(),
|
|
std::declval<SecondHalfTuple>()
|
|
));
|
|
};
|
|
|
|
template <typename Tuple>
|
|
using AppResultForTuple =
|
|
typename AppResultForTupleHelper<nbOooOrBinder, decltype(drop<0>(std::declval<Tuple>()))>::type;
|
|
|
|
template <typename RangeType>
|
|
using RangeTuple = std::conditional_t<nbOooOrBinder == 1, std::tuple<SubrangeT<RangeType>>, std::tuple<>>;
|
|
|
|
template <typename RangeType>
|
|
using AppResultForRangeType = decltype(std::tuple_cat(
|
|
std::declval<RangeTuple<RangeType>>(),
|
|
std::declval<
|
|
typename PatternTraits<Patterns>::template AppResultTuple<decltype(*std::begin(std::declval<RangeType>()))>>(
|
|
)...
|
|
));
|
|
|
|
template <typename Value, typename = std::void_t<>>
|
|
class AppResultHelper;
|
|
|
|
template <typename Value>
|
|
class AppResultHelper<Value, std::enable_if_t<isTupleLikeV<Value>>> {
|
|
public:
|
|
using type = AppResultForTuple<Value>;
|
|
};
|
|
|
|
template <typename RangeType>
|
|
class AppResultHelper<RangeType, std::enable_if_t<!isTupleLikeV<RangeType> && isRangeV<RangeType>>> {
|
|
public:
|
|
using type = AppResultForRangeType<RangeType>;
|
|
};
|
|
|
|
template <typename Value>
|
|
using AppResultTuple = typename AppResultHelper<Value>::type;
|
|
|
|
constexpr static auto nbIdV = (PatternTraits<Patterns>::nbIdV + ... + 0);
|
|
|
|
template <typename ValueTuple, typename ContextT>
|
|
constexpr static auto
|
|
matchPatternImpl(ValueTuple&& valueTuple, const Ds<Patterns...>& dsPat, int32_t depth, ContextT& context)
|
|
-> std::enable_if_t<isTupleLikeV<ValueTuple>, bool> {
|
|
if constexpr (nbOooOrBinder == 0) {
|
|
return std::apply(
|
|
[&valueTuple, depth, &context](const auto&... patterns) {
|
|
return apply_(
|
|
[depth, &context, &patterns...]<typename... T>(T&&... values) constexpr {
|
|
static_assert(sizeof...(patterns) == sizeof...(values));
|
|
return (matchPattern(std::forward<T>(values), patterns, depth + 1, context) && ...);
|
|
},
|
|
valueTuple
|
|
);
|
|
},
|
|
dsPat.patterns()
|
|
);
|
|
} else if constexpr (nbOooOrBinder == 1) {
|
|
constexpr auto idxOoo = findOooIdx<typename Ds<Patterns...>::Type>();
|
|
constexpr auto isBinder = isOooBinderV<std::tuple_element_t<idxOoo, std::tuple<Patterns...>>>;
|
|
constexpr auto isArray = isArrayV<ValueTuple>;
|
|
auto result =
|
|
matchPatternMultiple<0, 0, idxOoo>(std::forward<ValueTuple>(valueTuple), dsPat.patterns(), depth, context);
|
|
constexpr auto valLen = std::tuple_size_v<std::decay_t<ValueTuple>>;
|
|
constexpr auto patLen = sizeof...(Patterns);
|
|
if constexpr (isArray) {
|
|
if constexpr (isBinder) {
|
|
const auto rangeSize = static_cast<long>(valLen - (patLen - 1));
|
|
context.emplace_back(makeSubrange(&valueTuple[idxOoo], &valueTuple[idxOoo] + rangeSize));
|
|
using type = decltype(makeSubrange(&valueTuple[idxOoo], &valueTuple[idxOoo] + rangeSize));
|
|
result = result &&
|
|
matchPattern(std::get<type>(context.back()), std::get<idxOoo>(dsPat.patterns()), depth, context);
|
|
}
|
|
} else {
|
|
static_assert(!isBinder);
|
|
}
|
|
return result &&
|
|
matchPatternMultiple<valLen - patLen + idxOoo + 1, idxOoo + 1, patLen - idxOoo - 1>(
|
|
std::forward<ValueTuple>(valueTuple), dsPat.patterns(), depth, context
|
|
);
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
template <typename ValueRange, typename ContextT>
|
|
constexpr static auto
|
|
matchPatternImpl(ValueRange&& valueRange, const Ds<Patterns...>& dsPat, int32_t depth, ContextT& context)
|
|
-> std::enable_if_t<!isTupleLikeV<ValueRange> && isRangeV<ValueRange>, bool> {
|
|
static_assert(nbOooOrBinder == 0 || nbOooOrBinder == 1);
|
|
constexpr auto nbPat = sizeof...(Patterns);
|
|
|
|
if constexpr (nbOooOrBinder == 0) {
|
|
// size mismatch for dynamic array is not an error;
|
|
if (valueRange.size() != nbPat) {
|
|
return false;
|
|
}
|
|
return matchPatternRange<0, nbPat>(std::begin(valueRange), dsPat.patterns(), depth, context);
|
|
} else if constexpr (nbOooOrBinder == 1) {
|
|
if (valueRange.size() < nbPat - 1) {
|
|
return false;
|
|
}
|
|
constexpr auto idxOoo = findOooIdx<typename Ds<Patterns...>::Type>();
|
|
constexpr auto isBinder = isOooBinderV<std::tuple_element_t<idxOoo, std::tuple<Patterns...>>>;
|
|
auto result = matchPatternRange<0, idxOoo>(std::begin(valueRange), dsPat.patterns(), depth, context);
|
|
const auto valLen = valueRange.size();
|
|
constexpr auto patLen = sizeof...(Patterns);
|
|
const auto beginOoo = std::next(std::begin(valueRange), idxOoo);
|
|
if constexpr (isBinder) {
|
|
const auto rangeSize = static_cast<long>(valLen - (patLen - 1));
|
|
const auto end = std::next(beginOoo, rangeSize);
|
|
context.emplace_back(makeSubrange(beginOoo, end));
|
|
using type = decltype(makeSubrange(beginOoo, end));
|
|
result = result &&
|
|
matchPattern(std::get<type>(context.back()), std::get<idxOoo>(dsPat.patterns()), depth, context);
|
|
}
|
|
const auto beginAfterOoo = std::next(beginOoo, static_cast<long>(valLen - patLen + 1));
|
|
return result &&
|
|
matchPatternRange<idxOoo + 1, patLen - idxOoo - 1>(beginAfterOoo, dsPat.patterns(), depth, context);
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
constexpr static void processIdImpl(const Ds<Patterns...>& dsPat, int32_t depth, IdProcess idProcess) {
|
|
return std::apply(
|
|
[depth, idProcess](auto&&... patterns) { return (processId(patterns, depth, idProcess), ...); },
|
|
dsPat.patterns()
|
|
);
|
|
}
|
|
};
|
|
|
|
static_assert(std::is_same_v<
|
|
PatternTraits<Ds<OooBinder<SubrangeT<const std::array<int32_t, 2>>>>>::AppResultTuple<
|
|
const std::array<int32_t, 2>>,
|
|
std::tuple<matchit::impl::Subrange<const int32_t*>>>);
|
|
|
|
static_assert(std::is_same_v<
|
|
PatternTraits<Ds<OooBinder<Subrange<int32_t*>>, matchit::impl::Id<int32_t>>>::AppResultTuple<
|
|
const std::array<int32_t, 3>>,
|
|
std::tuple<matchit::impl::Subrange<const int32_t*>>>);
|
|
|
|
static_assert(std::is_same_v<
|
|
PatternTraits<Ds<OooBinder<Subrange<int32_t*>>, matchit::impl::Id<int32_t>>>::AppResultTuple<
|
|
std::array<int32_t, 3>>,
|
|
std::tuple<matchit::impl::Subrange<int32_t*>>>);
|
|
|
|
template <typename Pattern, typename Pred>
|
|
class PostCheck {
|
|
public:
|
|
constexpr explicit PostCheck(const Pattern& pattern, const Pred& pred)
|
|
: mPattern { pattern }, mPred { pred } {}
|
|
constexpr bool check() const {
|
|
return mPred();
|
|
}
|
|
constexpr const auto& pattern() const {
|
|
return mPattern;
|
|
}
|
|
|
|
private:
|
|
const Pattern mPattern;
|
|
const Pred mPred;
|
|
};
|
|
|
|
template <typename Pattern, typename Pred>
|
|
class PatternTraits<PostCheck<Pattern, Pred>> {
|
|
public:
|
|
template <typename Value>
|
|
using AppResultTuple = typename PatternTraits<Pattern>::template AppResultTuple<Value>;
|
|
|
|
template <typename Value, typename ContextT>
|
|
constexpr static auto matchPatternImpl(
|
|
Value&& value,
|
|
const PostCheck<Pattern, Pred>& postCheck,
|
|
const int32_t depth,
|
|
ContextT& context
|
|
) {
|
|
return matchPattern(std::forward<Value>(value), postCheck.pattern(), depth + 1, context) && postCheck.check();
|
|
}
|
|
constexpr static void
|
|
processIdImpl(const PostCheck<Pattern, Pred>& postCheck, int32_t depth, IdProcess idProcess) {
|
|
processId(postCheck.pattern(), depth, idProcess);
|
|
}
|
|
};
|
|
|
|
static_assert(std::is_same_v<PatternTraits<Wildcard>::AppResultTuple<int32_t>, std::tuple<>>);
|
|
static_assert(std::is_same_v<PatternTraits<int32_t>::AppResultTuple<int32_t>, std::tuple<>>);
|
|
constexpr auto x = [](auto&& t) { return t; };
|
|
static_assert(std::is_same_v<
|
|
PatternTraits<App<decltype(x), Wildcard>>::AppResultTuple<std::array<int32_t, 3>>,
|
|
std::tuple<std::array<int32_t, 3>>>);
|
|
|
|
static_assert(PatternTraits<And<App<decltype(x), Wildcard>>>::nbIdV == 0);
|
|
static_assert(PatternTraits<And<App<decltype(x), Id<int32_t>>>>::nbIdV == 1);
|
|
static_assert(PatternTraits<And<Id<int32_t>, Id<float>>>::nbIdV == 2);
|
|
static_assert(PatternTraits<Or<Id<int32_t>, Id<float>>>::nbIdV == 2);
|
|
static_assert(PatternTraits<Or<Wildcard, float>>::nbIdV == 0);
|
|
|
|
template <typename Value, typename... PatternPairs>
|
|
constexpr auto matchPatterns(Value&& value, const PatternPairs&... patterns) {
|
|
using RetType = typename PatternPairsRetType<PatternPairs...>::RetType;
|
|
using TypeTuple = decltype(std::tuple_cat(
|
|
std::declval<typename PatternTraits<typename PatternPairs::PatternT>::template AppResultTuple<Value>>()...
|
|
));
|
|
|
|
// expression, has return value.
|
|
if constexpr (!std::is_same_v<RetType, void>) {
|
|
constexpr auto func = [](const auto& pattern, auto&& val, RetType& result) constexpr -> bool {
|
|
if (auto context = typename ContextTrait<TypeTuple>::ContextT {};
|
|
pattern.matchValue(std::forward<Value>(val), context)) {
|
|
result = pattern.execute();
|
|
processId(pattern, 0, IdProcess::kCANCEL);
|
|
return true;
|
|
}
|
|
return false;
|
|
};
|
|
RetType result {};
|
|
const bool matched = (func(patterns, value, result) || ...);
|
|
if (!matched) {
|
|
throw std::logic_error { "Error: no patterns got matched!" };
|
|
}
|
|
static_cast<void>(matched);
|
|
return result;
|
|
} else
|
|
// statement, no return value, mismatching all patterns is not an error.
|
|
{
|
|
const auto func = [](const auto& pattern, auto&& val) -> bool {
|
|
if (auto context = typename ContextTrait<TypeTuple>::ContextT {};
|
|
pattern.matchValue(std::forward<Value>(val), context)) {
|
|
pattern.execute();
|
|
processId(pattern, 0, IdProcess::kCANCEL);
|
|
return true;
|
|
}
|
|
return false;
|
|
};
|
|
const bool matched = (func(patterns, value) || ...);
|
|
static_cast<void>(matched);
|
|
}
|
|
}
|
|
|
|
} // namespace impl
|
|
|
|
// export symbols
|
|
using impl::_;
|
|
using impl::and_;
|
|
using impl::app;
|
|
using impl::ds;
|
|
using impl::Id;
|
|
using impl::is;
|
|
using impl::meet;
|
|
using impl::not_;
|
|
using impl::ooo;
|
|
using impl::or_;
|
|
using impl::Subrange;
|
|
using impl::SubrangeT;
|
|
using impl::when;
|
|
} // namespace matchit
|
|
|
|
#endif // MATCHIT_PATTERNS_H
|
|
#ifndef MATCHIT_UTILITY_H
|
|
#define MATCHIT_UTILITY_H
|
|
|
|
#include <any>
|
|
|
|
namespace matchit {
|
|
namespace impl {
|
|
|
|
template <typename T>
|
|
constexpr auto cast = [](auto&& input) { return static_cast<T>(input); };
|
|
|
|
constexpr auto deref = [](auto&& x) -> decltype(*x)& { return *x; };
|
|
constexpr auto some = [](const auto pat) { return and_(app(cast<bool>, true), app(deref, pat)); };
|
|
|
|
constexpr auto none = app(cast<bool>, false);
|
|
|
|
template <typename Value, typename Variant, typename = std::void_t<>>
|
|
struct ViaGetIf : std::false_type {};
|
|
|
|
using std::get_if;
|
|
|
|
template <typename T, typename Variant>
|
|
struct ViaGetIf<T, Variant, std::void_t<decltype(get_if<T>(std::declval<const Variant*>()))>> : std::true_type {};
|
|
|
|
template <typename T, typename Variant>
|
|
constexpr auto viaGetIfV = ViaGetIf<T, Variant>::value;
|
|
|
|
static_assert(viaGetIfV<int, std::variant<int, bool>>);
|
|
|
|
template <typename T>
|
|
class AsPointer {
|
|
static_assert(!std::is_reference_v<T>);
|
|
|
|
public:
|
|
template <typename Variant, std::enable_if_t<viaGetIfV<T, std::decay_t<Variant>>>* = nullptr>
|
|
constexpr auto operator()(Variant&& v) const {
|
|
return get_if<T>(std::addressof(v));
|
|
}
|
|
|
|
// template to disable implicit cast to std::any
|
|
template <typename A, std::enable_if_t<std::is_same_v<std::decay_t<A>, std::any>>* = nullptr>
|
|
constexpr auto operator()(A&& a) const {
|
|
return std::any_cast<T>(std::addressof(a));
|
|
}
|
|
|
|
// cast to base class
|
|
template <typename D, std::enable_if_t<!viaGetIfV<T, D> && std::is_base_of_v<T, D>>* = nullptr>
|
|
constexpr auto operator()(const D& d) const -> decltype(static_cast<const T*>(std::addressof(d))) {
|
|
return static_cast<const T*>(std::addressof(d));
|
|
}
|
|
|
|
// No way to handle rvalue to save copy in this class. Need to define some in another way to handle this.
|
|
// cast to base class
|
|
template <typename D, std::enable_if_t<!viaGetIfV<T, D> && std::is_base_of_v<T, D>>* = nullptr>
|
|
constexpr auto operator()(D& d) const -> decltype(static_cast<T*>(std::addressof(d))) {
|
|
return static_cast<T*>(std::addressof(d));
|
|
}
|
|
|
|
// cast to derived class
|
|
template <typename B, std::enable_if_t<!viaGetIfV<T, B> && std::is_base_of_v<B, T>>* = nullptr>
|
|
constexpr auto operator()(const B& b) const -> decltype(dynamic_cast<const T*>(std::addressof(b))) {
|
|
return dynamic_cast<const T*>(std::addressof(b));
|
|
}
|
|
|
|
// cast to derived class
|
|
template <typename B, std::enable_if_t<!viaGetIfV<T, B> && std::is_base_of_v<B, T>>* = nullptr>
|
|
constexpr auto operator()(B& b) const -> decltype(dynamic_cast<T*>(std::addressof(b))) {
|
|
return dynamic_cast<T*>(std::addressof(b));
|
|
}
|
|
|
|
constexpr auto operator()(const T& b) const {
|
|
return std::addressof(b);
|
|
}
|
|
|
|
constexpr auto operator()(T& b) const {
|
|
return std::addressof(b);
|
|
}
|
|
};
|
|
|
|
static_assert(std::is_invocable_v<AsPointer<int>, int>);
|
|
static_assert(std::is_invocable_v<AsPointer<std::tuple<int>>, std::tuple<int>>);
|
|
|
|
template <typename T>
|
|
constexpr AsPointer<T> asPointer;
|
|
|
|
template <typename T>
|
|
constexpr auto as = [](const auto pat) { return app(asPointer<T>, some(pat)); };
|
|
|
|
template <typename Value, typename Pattern>
|
|
constexpr auto matched(Value&& v, Pattern&& p) {
|
|
return match(std::forward<Value>(v))(
|
|
is | std::forward<Pattern>(p) = [] { return true; }, is | _ = [] { return false; }
|
|
);
|
|
}
|
|
|
|
constexpr auto dsVia = [](auto... members) {
|
|
return [members...](auto... pats) { return and_(app(members, pats)...); };
|
|
};
|
|
|
|
template <typename T>
|
|
constexpr auto asDsVia =
|
|
[](auto... members) { return [members...](auto... pats) { return as<T>(and_(app(members, pats)...)); }; };
|
|
|
|
} // namespace impl
|
|
using impl::as;
|
|
using impl::asDsVia;
|
|
using impl::dsVia;
|
|
using impl::matched;
|
|
using impl::none;
|
|
using impl::some;
|
|
// NOLINTEND(*-identifier-naming)
|
|
} // namespace matchit
|
|
|
|
#endif // MATCHIT_UTILITY_H
|
|
|
|
#endif // MATCHIT_H
|