2 * Copyright 2016 Facebook, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
20 #include <boost/iterator/iterator_adaptor.hpp>
21 #include <boost/iterator/iterator_facade.hpp>
22 #include <folly/Likely.h>
23 #include <folly/Conv.h>
24 #include <folly/Format.h>
26 //////////////////////////////////////////////////////////////////////
31 struct hash< ::folly::dynamic> {
32 size_t operator()(::folly::dynamic const& d) const {
39 //////////////////////////////////////////////////////////////////////
41 // This is a higher-order preprocessor macro to aid going from runtime
42 // types to the compile time type system.
43 #define FB_DYNAMIC_APPLY(type, apply) \
73 //////////////////////////////////////////////////////////////////////
77 struct TypeError : std::runtime_error {
78 explicit TypeError(const std::string& expected, dynamic::Type actual);
79 explicit TypeError(const std::string& expected,
80 dynamic::Type actual1, dynamic::Type actual2);
85 //////////////////////////////////////////////////////////////////////
89 // This helper is used in destroy() to be able to run destructors on
90 // types like "int64_t" without a compiler error.
92 template<class T> static void destroy(T* t) { t->~T(); }
96 * The enable_if junk here is necessary to avoid ambiguous
97 * conversions relating to bool and double when you implicitly
98 * convert an int or long to a dynamic.
100 template<class T, class Enable = void> struct ConversionHelper;
102 struct ConversionHelper<
104 typename std::enable_if<
105 std::is_integral<T>::value && !std::is_same<T,bool>::value
108 typedef int64_t type;
111 struct ConversionHelper<
113 typename std::enable_if<
114 (!std::is_integral<T>::value || std::is_same<T,bool>::value) &&
115 !std::is_same<T,std::nullptr_t>::value
121 struct ConversionHelper<
123 typename std::enable_if<
124 std::is_same<T,std::nullptr_t>::value
131 * Helper for implementing numeric conversions in operators on
132 * numbers. Just promotes to double when one of the arguments is
133 * double, or throws if either is not a numeric type.
135 template<template<class> class Op>
136 dynamic numericOp(dynamic const& a, dynamic const& b) {
137 if (!a.isNumber() || !b.isNumber()) {
138 throw TypeError("numeric", a.type(), b.type());
140 if (a.type() != b.type()) {
141 auto& integ = a.isInt() ? a : b;
142 auto& nonint = a.isInt() ? b : a;
143 return Op<double>()(to<double>(integ.asInt()), nonint.asDouble());
146 return Op<double>()(a.asDouble(), b.asDouble());
148 return Op<int64_t>()(a.asInt(), b.asInt());
153 //////////////////////////////////////////////////////////////////////
156 * We're doing this instead of a simple member typedef to avoid the
157 * undefined behavior of parameterizing std::unordered_map<> with an
160 * Note: Later we may add separate order tracking here (a multi-index
163 struct dynamic::ObjectImpl : std::unordered_map<dynamic, dynamic> {};
165 //////////////////////////////////////////////////////////////////////
167 // Helper object for creating objects conveniently. See object and
168 // the dynamic::dynamic(ObjectMaker&&) ctor.
169 struct dynamic::ObjectMaker {
170 friend struct dynamic;
172 explicit ObjectMaker() : val_(dynamic::object) {}
173 explicit ObjectMaker(dynamic const& key, dynamic val)
174 : val_(dynamic::object)
176 val_.insert(key, std::move(val));
178 explicit ObjectMaker(dynamic&& key, dynamic val)
179 : val_(dynamic::object)
181 val_.insert(std::move(key), std::move(val));
184 // Make sure no one tries to save one of these into an lvalue with
185 // auto or anything like that.
186 ObjectMaker(ObjectMaker&&) = default;
187 ObjectMaker(ObjectMaker const&) = delete;
188 ObjectMaker& operator=(ObjectMaker const&) = delete;
189 ObjectMaker& operator=(ObjectMaker&&) = delete;
191 // These return rvalue-references instead of lvalue-references to allow
192 // constructs like this to moved instead of copied:
193 // dynamic a = dynamic::object("a", "b")("c", "d")
194 ObjectMaker&& operator()(dynamic const& key, dynamic val) {
195 val_.insert(key, std::move(val));
196 return std::move(*this);
199 ObjectMaker&& operator()(dynamic&& key, dynamic val) {
200 val_.insert(std::move(key), std::move(val));
201 return std::move(*this);
208 inline void dynamic::array(EmptyArrayTag) {}
210 template <class... Args>
211 inline dynamic dynamic::array(Args&& ...args) {
212 return dynamic(Array{std::forward<Args>(args)...}, PrivateTag());
215 // This looks like a case for perfect forwarding, but our use of
216 // std::initializer_list for constructing dynamic arrays makes it less
217 // functional than doing this manually.
219 // TODO(ott, 10300209): When the initializer_list constructor is gone,
221 inline dynamic::ObjectMaker dynamic::object() { return ObjectMaker(); }
222 inline dynamic::ObjectMaker dynamic::object(dynamic&& a, dynamic&& b) {
223 return ObjectMaker(std::move(a), std::move(b));
225 inline dynamic::ObjectMaker dynamic::object(dynamic const& a, dynamic&& b) {
226 return ObjectMaker(a, std::move(b));
228 inline dynamic::ObjectMaker dynamic::object(dynamic&& a, dynamic const& b) {
229 return ObjectMaker(std::move(a), b);
231 inline dynamic::ObjectMaker
232 dynamic::object(dynamic const& a, dynamic const& b) {
233 return ObjectMaker(a, b);
236 //////////////////////////////////////////////////////////////////////
238 struct dynamic::const_item_iterator
239 : boost::iterator_adaptor<dynamic::const_item_iterator,
240 dynamic::ObjectImpl::const_iterator> {
241 /* implicit */ const_item_iterator(base_type b) : iterator_adaptor_(b) { }
244 friend class boost::iterator_core_access;
247 struct dynamic::const_key_iterator
248 : boost::iterator_adaptor<dynamic::const_key_iterator,
249 dynamic::ObjectImpl::const_iterator,
251 /* implicit */ const_key_iterator(base_type b) : iterator_adaptor_(b) { }
254 dynamic const& dereference() const {
255 return base_reference()->first;
257 friend class boost::iterator_core_access;
260 struct dynamic::const_value_iterator
261 : boost::iterator_adaptor<dynamic::const_value_iterator,
262 dynamic::ObjectImpl::const_iterator,
264 /* implicit */ const_value_iterator(base_type b) : iterator_adaptor_(b) { }
267 dynamic const& dereference() const {
268 return base_reference()->second;
270 friend class boost::iterator_core_access;
273 //////////////////////////////////////////////////////////////////////
275 inline dynamic::dynamic(void (*)(EmptyArrayTag))
278 new (&u_.array) Array();
281 inline dynamic::dynamic(ObjectMaker (*)())
284 new (getAddress<ObjectImpl>()) ObjectImpl();
287 inline dynamic::dynamic(StringPiece s)
290 new (&u_.string) std::string(s.data(), s.size());
293 inline dynamic::dynamic(char const* s)
296 new (&u_.string) std::string(s);
299 inline dynamic::dynamic(std::string const& s)
302 new (&u_.string) std::string(s);
305 inline dynamic::dynamic(std::string&& s) : type_(STRING) {
306 new (&u_.string) std::string(std::move(s));
309 inline dynamic::dynamic(std::initializer_list<dynamic> il)
310 : dynamic(Array(std::move(il)), PrivateTag()) {}
312 inline dynamic& dynamic::operator=(std::initializer_list<dynamic> il) {
313 (*this) = dynamic(Array(std::move(il)), PrivateTag());
317 inline dynamic::dynamic(ObjectMaker&& maker)
320 new (getAddress<ObjectImpl>())
321 ObjectImpl(std::move(*maker.val_.getAddress<ObjectImpl>()));
324 inline dynamic::dynamic(dynamic const& o)
330 inline dynamic::dynamic(dynamic&& o) noexcept
333 *this = std::move(o);
336 inline dynamic::~dynamic() noexcept { destroy(); }
339 dynamic::dynamic(T t) {
340 typedef typename detail::ConversionHelper<T>::type U;
341 type_ = TypeInfo<U>::type;
342 new (getAddress<U>()) U(std::move(t));
345 template<class Iterator>
346 dynamic::dynamic(Iterator first, Iterator last)
349 new (&u_.array) Array(first, last);
352 //////////////////////////////////////////////////////////////////////
354 inline dynamic::const_iterator dynamic::begin() const {
355 return get<Array>().begin();
357 inline dynamic::const_iterator dynamic::end() const {
358 return get<Array>().end();
362 struct dynamic::IterableProxy {
363 typedef It const_iterator;
364 typedef typename It::value_type value_type;
366 /* implicit */ IterableProxy(const dynamic::ObjectImpl* o) : o_(o) { }
377 const dynamic::ObjectImpl* o_;
380 inline dynamic::IterableProxy<dynamic::const_key_iterator> dynamic::keys()
382 return &(get<ObjectImpl>());
385 inline dynamic::IterableProxy<dynamic::const_value_iterator> dynamic::values()
387 return &(get<ObjectImpl>());
390 inline dynamic::IterableProxy<dynamic::const_item_iterator> dynamic::items()
392 return &(get<ObjectImpl>());
395 inline bool dynamic::isString() const {
396 return get_nothrow<std::string>();
398 inline bool dynamic::isObject() const { return get_nothrow<ObjectImpl>(); }
399 inline bool dynamic::isBool() const { return get_nothrow<bool>(); }
400 inline bool dynamic::isArray() const { return get_nothrow<Array>(); }
401 inline bool dynamic::isDouble() const { return get_nothrow<double>(); }
402 inline bool dynamic::isInt() const { return get_nothrow<int64_t>(); }
403 inline bool dynamic::isNull() const { return get_nothrow<void*>(); }
404 inline bool dynamic::isNumber() const { return isInt() || isDouble(); }
406 inline dynamic::Type dynamic::type() const {
410 inline std::string dynamic::asString() const {
411 return asImpl<std::string>();
413 inline double dynamic::asDouble() const {
414 return asImpl<double>();
416 inline int64_t dynamic::asInt() const {
417 return asImpl<int64_t>();
419 inline bool dynamic::asBool() const {
420 return asImpl<bool>();
423 inline const std::string& dynamic::getString() const& {
424 return get<std::string>();
426 inline double dynamic::getDouble() const& { return get<double>(); }
427 inline int64_t dynamic::getInt() const& { return get<int64_t>(); }
428 inline bool dynamic::getBool() const& { return get<bool>(); }
430 inline std::string& dynamic::getString()& {
431 return get<std::string>();
433 inline double& dynamic::getDouble() & { return get<double>(); }
434 inline int64_t& dynamic::getInt() & { return get<int64_t>(); }
435 inline bool& dynamic::getBool() & { return get<bool>(); }
437 inline std::string dynamic::getString()&& {
438 return std::move(get<std::string>());
440 inline double dynamic::getDouble() && { return get<double>(); }
441 inline int64_t dynamic::getInt() && { return get<int64_t>(); }
442 inline bool dynamic::getBool() && { return get<bool>(); }
444 inline const char* dynamic::data() const& {
445 return get<std::string>().data();
447 inline const char* dynamic::c_str() const& {
448 return get<std::string>().c_str();
450 inline StringPiece dynamic::stringPiece() const {
451 return get<std::string>();
455 struct dynamic::CompareOp {
456 static bool comp(T const& a, T const& b) { return a < b; }
459 struct dynamic::CompareOp<dynamic::ObjectImpl> {
460 static bool comp(ObjectImpl const&, ObjectImpl const&) {
461 // This code never executes; it is just here for the compiler.
466 inline dynamic& dynamic::operator+=(dynamic const& o) {
467 if (type() == STRING && o.type() == STRING) {
468 *getAddress<std::string>() += *o.getAddress<std::string>();
471 *this = detail::numericOp<std::plus>(*this, o);
475 inline dynamic& dynamic::operator-=(dynamic const& o) {
476 *this = detail::numericOp<std::minus>(*this, o);
480 inline dynamic& dynamic::operator*=(dynamic const& o) {
481 *this = detail::numericOp<std::multiplies>(*this, o);
485 inline dynamic& dynamic::operator/=(dynamic const& o) {
486 *this = detail::numericOp<std::divides>(*this, o);
490 #define FB_DYNAMIC_INTEGER_OP(op) \
491 inline dynamic& dynamic::operator op(dynamic const& o) { \
492 if (!isInt() || !o.isInt()) { \
493 throw TypeError("int64", type(), o.type()); \
495 *getAddress<int64_t>() op o.asInt(); \
499 FB_DYNAMIC_INTEGER_OP(%=)
500 FB_DYNAMIC_INTEGER_OP(|=)
501 FB_DYNAMIC_INTEGER_OP(&=)
502 FB_DYNAMIC_INTEGER_OP(^=)
504 #undef FB_DYNAMIC_INTEGER_OP
506 inline dynamic& dynamic::operator++() {
511 inline dynamic& dynamic::operator--() {
516 inline dynamic const& dynamic::operator[](dynamic const& idx) const& {
520 inline dynamic dynamic::operator[](dynamic const& idx) && {
521 return std::move((*this)[idx]);
524 template<class K, class V> inline dynamic& dynamic::setDefault(K&& k, V&& v) {
525 auto& obj = get<ObjectImpl>();
526 return obj.insert(std::make_pair(std::forward<K>(k),
527 std::forward<V>(v))).first->second;
530 inline dynamic* dynamic::get_ptr(dynamic const& idx) & {
531 return const_cast<dynamic*>(const_cast<dynamic const*>(this)->get_ptr(idx));
534 inline dynamic& dynamic::at(dynamic const& idx) & {
535 return const_cast<dynamic&>(const_cast<dynamic const*>(this)->at(idx));
538 inline dynamic dynamic::at(dynamic const& idx) && {
539 return std::move(at(idx));
542 inline bool dynamic::empty() const {
549 inline std::size_t dynamic::count(dynamic const& key) const {
550 return find(key) != items().end();
553 inline dynamic::const_item_iterator dynamic::find(dynamic const& key) const {
554 return get<ObjectImpl>().find(key);
557 template<class K, class V> inline void dynamic::insert(K&& key, V&& val) {
558 auto& obj = get<ObjectImpl>();
559 auto rv = obj.insert({ std::forward<K>(key), nullptr });
560 rv.first->second = std::forward<V>(val);
563 inline void dynamic::update(const dynamic& mergeObj) {
564 if (!isObject() || !mergeObj.isObject()) {
565 throw TypeError("object", type(), mergeObj.type());
568 for (const auto& pair : mergeObj.items()) {
569 (*this)[pair.first] = pair.second;
573 inline void dynamic::update_missing(const dynamic& mergeObj1) {
574 if (!isObject() || !mergeObj1.isObject()) {
575 throw TypeError("object", type(), mergeObj1.type());
578 // Only add if not already there
579 for (const auto& pair : mergeObj1.items()) {
580 if ((*this).find(pair.first) == (*this).items().end()) {
581 (*this)[pair.first] = pair.second;
586 inline dynamic dynamic::merge(
587 const dynamic& mergeObj1,
588 const dynamic& mergeObj2) {
590 // No checks on type needed here because they are done in update_missing
591 // Note that we do update_missing here instead of update() because
592 // it will prevent the extra writes that would occur with update()
593 auto ret = mergeObj2;
594 ret.update_missing(mergeObj1);
598 inline std::size_t dynamic::erase(dynamic const& key) {
599 auto& obj = get<ObjectImpl>();
600 return obj.erase(key);
603 inline dynamic::const_iterator dynamic::erase(const_iterator it) {
604 auto& arr = get<Array>();
605 // std::vector doesn't have an erase method that works on const iterators,
606 // even though the standard says it should, so this hack converts to a
607 // non-const iterator before calling erase.
608 return get<Array>().erase(arr.begin() + (it - arr.begin()));
611 inline dynamic::const_key_iterator dynamic::erase(const_key_iterator it) {
612 return const_key_iterator(get<ObjectImpl>().erase(it.base()));
615 inline dynamic::const_key_iterator dynamic::erase(const_key_iterator first,
616 const_key_iterator last) {
617 return const_key_iterator(get<ObjectImpl>().erase(first.base(),
621 inline dynamic::const_value_iterator dynamic::erase(const_value_iterator it) {
622 return const_value_iterator(get<ObjectImpl>().erase(it.base()));
625 inline dynamic::const_value_iterator dynamic::erase(const_value_iterator first,
626 const_value_iterator last) {
627 return const_value_iterator(get<ObjectImpl>().erase(first.base(),
631 inline dynamic::const_item_iterator dynamic::erase(const_item_iterator it) {
632 return const_item_iterator(get<ObjectImpl>().erase(it.base()));
635 inline dynamic::const_item_iterator dynamic::erase(const_item_iterator first,
636 const_item_iterator last) {
637 return const_item_iterator(get<ObjectImpl>().erase(first.base(),
641 inline void dynamic::resize(std::size_t sz, dynamic const& c) {
642 auto& arr = get<Array>();
646 inline void dynamic::push_back(dynamic const& v) {
647 auto& arr = get<Array>();
651 inline void dynamic::push_back(dynamic&& v) {
652 auto& arr = get<Array>();
653 arr.push_back(std::move(v));
656 inline void dynamic::pop_back() {
657 auto& arr = get<Array>();
661 //////////////////////////////////////////////////////////////////////
663 inline dynamic::dynamic(Array&& r, PrivateTag) : type_(ARRAY) {
664 new (&u_.array) Array(std::move(r));
667 #define FOLLY_DYNAMIC_DEC_TYPEINFO(T, str, val) \
668 template <> struct dynamic::TypeInfo<T> { \
669 static constexpr const char* name = str; \
670 static constexpr dynamic::Type type = val; \
674 FOLLY_DYNAMIC_DEC_TYPEINFO(void*, "null", dynamic::NULLT)
675 FOLLY_DYNAMIC_DEC_TYPEINFO(bool, "boolean", dynamic::BOOL)
676 FOLLY_DYNAMIC_DEC_TYPEINFO(std::string, "string", dynamic::STRING)
677 FOLLY_DYNAMIC_DEC_TYPEINFO(dynamic::Array, "array", dynamic::ARRAY)
678 FOLLY_DYNAMIC_DEC_TYPEINFO(double, "double", dynamic::DOUBLE)
679 FOLLY_DYNAMIC_DEC_TYPEINFO(int64_t, "int64", dynamic::INT64)
680 FOLLY_DYNAMIC_DEC_TYPEINFO(dynamic::ObjectImpl, "object", dynamic::OBJECT)
682 #undef FOLLY_DYNAMIC_DEC_TYPEINFO
685 T dynamic::asImpl() const {
687 case INT64: return to<T>(*get_nothrow<int64_t>());
688 case DOUBLE: return to<T>(*get_nothrow<double>());
689 case BOOL: return to<T>(*get_nothrow<bool>());
691 return to<T>(*get_nothrow<std::string>());
693 throw TypeError("int/double/bool/string", type());
697 // Return a T* to our type, or null if we're not that type.
699 T* dynamic::get_nothrow() & noexcept {
700 if (type_ != TypeInfo<T>::type) {
703 return getAddress<T>();
707 T const* dynamic::get_nothrow() const& noexcept {
708 return const_cast<dynamic*>(this)->get_nothrow<T>();
711 // Return T* for where we can put a T, without type checking. (Memory
712 // might be uninitialized, even.)
714 T* dynamic::getAddress() noexcept {
715 return GetAddrImpl<T>::get(u_);
719 T const* dynamic::getAddress() const noexcept {
720 return const_cast<dynamic*>(this)->getAddress<T>();
723 template<class T> struct dynamic::GetAddrImpl {};
724 template<> struct dynamic::GetAddrImpl<void*> {
725 static void** get(Data& d) noexcept { return &d.nul; }
727 template<> struct dynamic::GetAddrImpl<dynamic::Array> {
728 static Array* get(Data& d) noexcept { return &d.array; }
730 template<> struct dynamic::GetAddrImpl<bool> {
731 static bool* get(Data& d) noexcept { return &d.boolean; }
733 template<> struct dynamic::GetAddrImpl<int64_t> {
734 static int64_t* get(Data& d) noexcept { return &d.integer; }
736 template<> struct dynamic::GetAddrImpl<double> {
737 static double* get(Data& d) noexcept { return &d.doubl; }
740 struct dynamic::GetAddrImpl<std::string> {
741 static std::string* get(Data& d) noexcept {
745 template<> struct dynamic::GetAddrImpl<dynamic::ObjectImpl> {
746 static_assert(sizeof(ObjectImpl) <= sizeof(Data::objectBuffer),
747 "In your implementation, std::unordered_map<> apparently takes different"
748 " amount of space depending on its template parameters. This is "
749 "weird. Make objectBuffer bigger if you want to compile dynamic.");
751 static ObjectImpl* get(Data& d) noexcept {
752 void* data = &d.objectBuffer;
753 return static_cast<ObjectImpl*>(data);
759 if (auto* p = get_nothrow<T>()) {
762 throw TypeError(TypeInfo<T>::name, type());
766 T const& dynamic::get() const {
767 return const_cast<dynamic*>(this)->get<T>();
770 //////////////////////////////////////////////////////////////////////
773 * Helper for implementing operator<<. Throws if the type shouldn't
777 struct dynamic::PrintImpl {
778 static void print(dynamic const&, std::ostream& out, T const& t) {
782 // Otherwise, null, being (void*)0, would print as 0.
784 struct dynamic::PrintImpl<void*> {
785 static void print(dynamic const& /* d */,
788 DCHECK_EQ((void*)0, nul);
793 struct dynamic::PrintImpl<dynamic::ObjectImpl> {
794 static void print(dynamic const& d,
796 dynamic::ObjectImpl const&) {
797 d.print_as_pseudo_json(out);
801 struct dynamic::PrintImpl<dynamic::Array> {
802 static void print(dynamic const& d,
804 dynamic::Array const&) {
805 d.print_as_pseudo_json(out);
809 inline void dynamic::print(std::ostream& out) const {
810 #define FB_X(T) PrintImpl<T>::print(*this, out, *getAddress<T>())
811 FB_DYNAMIC_APPLY(type_, FB_X);
815 inline std::ostream& operator<<(std::ostream& out, dynamic const& d) {
820 //////////////////////////////////////////////////////////////////////
822 // Secialization of FormatValue so dynamic objects can be formatted
824 class FormatValue<dynamic> {
826 explicit FormatValue(const dynamic& val) : val_(val) { }
828 template <class FormatCallback>
829 void format(FormatArg& arg, FormatCallback& cb) const {
830 switch (val_.type()) {
832 FormatValue<std::nullptr_t>(nullptr).format(arg, cb);
835 FormatValue<bool>(val_.asBool()).format(arg, cb);
838 FormatValue<int64_t>(val_.asInt()).format(arg, cb);
840 case dynamic::STRING:
841 FormatValue<std::string>(val_.asString()).format(arg, cb);
843 case dynamic::DOUBLE:
844 FormatValue<double>(val_.asDouble()).format(arg, cb);
847 FormatValue(val_.at(arg.splitIntKey())).format(arg, cb);
849 case dynamic::OBJECT:
850 FormatValue(val_.at(arg.splitKey().toString())).format(arg, cb);
860 class FormatValue<detail::DefaultValueWrapper<dynamic, V>> {
862 explicit FormatValue(
863 const detail::DefaultValueWrapper<dynamic, V>& val)
866 template <class FormatCallback>
867 void format(FormatArg& arg, FormatCallback& cb) const {
868 auto& c = val_.container;
873 case dynamic::STRING:
874 case dynamic::DOUBLE:
875 FormatValue<dynamic>(c).format(arg, cb);
879 int key = arg.splitIntKey();
880 if (key >= 0 && size_t(key) < c.size()) {
881 FormatValue<dynamic>(c.at(key)).format(arg, cb);
883 FormatValue<V>(val_.defaultValue).format(arg, cb);
887 case dynamic::OBJECT:
889 auto pos = c.find(arg.splitKey());
890 if (pos != c.items().end()) {
891 FormatValue<dynamic>(pos->second).format(arg, cb);
893 FormatValue<V>(val_.defaultValue).format(arg, cb);
901 const detail::DefaultValueWrapper<dynamic, V>& val_;
906 #undef FB_DYNAMIC_APPLY