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// Copyright 2017 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef V8_OBJECTS_STRING_INL_H_
#define V8_OBJECTS_STRING_INL_H_
#include "src/objects/string.h"
#include "src/conversions-inl.h"
#include "src/handles-inl.h"
#include "src/heap/factory.h"
#include "src/objects/name-inl.h"
#include "src/string-hasher-inl.h"
// Has to be the last include (doesn't have include guards):
#include "src/objects/object-macros.h"
namespace v8 {
namespace internal {
SMI_ACCESSORS(String, length, kLengthOffset)
SYNCHRONIZED_SMI_ACCESSORS(String, length, kLengthOffset)
CAST_ACCESSOR(ConsString)
CAST_ACCESSOR(ExternalOneByteString)
CAST_ACCESSOR(ExternalString)
CAST_ACCESSOR(ExternalTwoByteString)
CAST_ACCESSOR(InternalizedString)
CAST_ACCESSOR(SeqOneByteString)
CAST_ACCESSOR(SeqString)
CAST_ACCESSOR(SeqTwoByteString)
CAST_ACCESSOR(SlicedString)
CAST_ACCESSOR(String)
CAST_ACCESSOR(ThinString)
StringShape::StringShape(const String* str)
: type_(str->map()->instance_type()) {
set_valid();
DCHECK_EQ(type_ & kIsNotStringMask, kStringTag);
}
StringShape::StringShape(Map* map) : type_(map->instance_type()) {
set_valid();
DCHECK_EQ(type_ & kIsNotStringMask, kStringTag);
}
StringShape::StringShape(InstanceType t) : type_(static_cast<uint32_t>(t)) {
set_valid();
DCHECK_EQ(type_ & kIsNotStringMask, kStringTag);
}
bool StringShape::IsInternalized() {
DCHECK(valid());
STATIC_ASSERT(kNotInternalizedTag != 0);
return (type_ & (kIsNotStringMask | kIsNotInternalizedMask)) ==
(kStringTag | kInternalizedTag);
}
bool StringShape::HasOnlyOneByteChars() {
return (type_ & kStringEncodingMask) == kOneByteStringTag ||
(type_ & kOneByteDataHintMask) == kOneByteDataHintTag;
}
bool StringShape::IsCons() {
return (type_ & kStringRepresentationMask) == kConsStringTag;
}
bool StringShape::IsThin() {
return (type_ & kStringRepresentationMask) == kThinStringTag;
}
bool StringShape::IsSliced() {
return (type_ & kStringRepresentationMask) == kSlicedStringTag;
}
bool StringShape::IsIndirect() {
return (type_ & kIsIndirectStringMask) == kIsIndirectStringTag;
}
bool StringShape::IsExternal() {
return (type_ & kStringRepresentationMask) == kExternalStringTag;
}
bool StringShape::IsSequential() {
return (type_ & kStringRepresentationMask) == kSeqStringTag;
}
StringRepresentationTag StringShape::representation_tag() {
uint32_t tag = (type_ & kStringRepresentationMask);
return static_cast<StringRepresentationTag>(tag);
}
uint32_t StringShape::encoding_tag() { return type_ & kStringEncodingMask; }
uint32_t StringShape::full_representation_tag() {
return (type_ & (kStringRepresentationMask | kStringEncodingMask));
}
STATIC_ASSERT((kStringRepresentationMask | kStringEncodingMask) ==
Internals::kFullStringRepresentationMask);
STATIC_ASSERT(static_cast<uint32_t>(kStringEncodingMask) ==
Internals::kStringEncodingMask);
bool StringShape::IsSequentialOneByte() {
return full_representation_tag() == (kSeqStringTag | kOneByteStringTag);
}
bool StringShape::IsSequentialTwoByte() {
return full_representation_tag() == (kSeqStringTag | kTwoByteStringTag);
}
bool StringShape::IsExternalOneByte() {
return full_representation_tag() == (kExternalStringTag | kOneByteStringTag);
}
STATIC_ASSERT((kExternalStringTag | kOneByteStringTag) ==
Internals::kExternalOneByteRepresentationTag);
STATIC_ASSERT(v8::String::ONE_BYTE_ENCODING == kOneByteStringTag);
bool StringShape::IsExternalTwoByte() {
return full_representation_tag() == (kExternalStringTag | kTwoByteStringTag);
}
STATIC_ASSERT((kExternalStringTag | kTwoByteStringTag) ==
Internals::kExternalTwoByteRepresentationTag);
STATIC_ASSERT(v8::String::TWO_BYTE_ENCODING == kTwoByteStringTag);
bool String::IsOneByteRepresentation() const {
uint32_t type = map()->instance_type();
return (type & kStringEncodingMask) == kOneByteStringTag;
}
bool String::IsTwoByteRepresentation() const {
uint32_t type = map()->instance_type();
return (type & kStringEncodingMask) == kTwoByteStringTag;
}
bool String::IsOneByteRepresentationUnderneath() {
uint32_t type = map()->instance_type();
STATIC_ASSERT(kIsIndirectStringTag != 0);
STATIC_ASSERT((kIsIndirectStringMask & kStringEncodingMask) == 0);
DCHECK(IsFlat());
switch (type & (kIsIndirectStringMask | kStringEncodingMask)) {
case kOneByteStringTag:
return true;
case kTwoByteStringTag:
return false;
default: // Cons or sliced string. Need to go deeper.
return GetUnderlying()->IsOneByteRepresentation();
}
}
bool String::IsTwoByteRepresentationUnderneath() {
uint32_t type = map()->instance_type();
STATIC_ASSERT(kIsIndirectStringTag != 0);
STATIC_ASSERT((kIsIndirectStringMask & kStringEncodingMask) == 0);
DCHECK(IsFlat());
switch (type & (kIsIndirectStringMask | kStringEncodingMask)) {
case kOneByteStringTag:
return false;
case kTwoByteStringTag:
return true;
default: // Cons or sliced string. Need to go deeper.
return GetUnderlying()->IsTwoByteRepresentation();
}
}
bool String::HasOnlyOneByteChars() {
uint32_t type = map()->instance_type();
return (type & kOneByteDataHintMask) == kOneByteDataHintTag ||
IsOneByteRepresentation();
}
uc32 FlatStringReader::Get(int index) {
if (is_one_byte_) {
return Get<uint8_t>(index);
} else {
return Get<uc16>(index);
}
}
template <typename Char>
Char FlatStringReader::Get(int index) {
DCHECK_EQ(is_one_byte_, sizeof(Char) == 1);
DCHECK(0 <= index && index <= length_);
if (sizeof(Char) == 1) {
return static_cast<Char>(static_cast<const uint8_t*>(start_)[index]);
} else {
return static_cast<Char>(static_cast<const uc16*>(start_)[index]);
}
}
template <typename Char>
class SequentialStringKey : public StringTableKey {
public:
explicit SequentialStringKey(Vector<const Char> string, uint64_t seed)
: StringTableKey(StringHasher::HashSequentialString<Char>(
string.start(), string.length(), seed)),
string_(string) {}
Vector<const Char> string_;
};
class OneByteStringKey : public SequentialStringKey<uint8_t> {
public:
OneByteStringKey(Vector<const uint8_t> str, uint64_t seed)
: SequentialStringKey<uint8_t>(str, seed) {}
bool IsMatch(Object* string) override {
return String::cast(string)->IsOneByteEqualTo(string_);
}
Handle<String> AsHandle(Isolate* isolate) override;
};
class SeqOneByteSubStringKey : public StringTableKey {
public:
// VS 2017 on official builds gives this spurious warning:
// warning C4789: buffer 'key' of size 16 bytes will be overrun; 4 bytes will
// be written starting at offset 16
// https://bugs.chromium.org/p/v8/issues/detail?id=6068
#if defined(V8_CC_MSVC)
#pragma warning(push)
#pragma warning(disable : 4789)
#endif
SeqOneByteSubStringKey(Isolate* isolate, Handle<SeqOneByteString> string,
int from, int length)
: StringTableKey(StringHasher::HashSequentialString(
string->GetChars() + from, length, isolate->heap()->HashSeed())),
string_(string),
from_(from),
length_(length) {
DCHECK_LE(0, length_);
DCHECK_LE(from_ + length_, string_->length());
DCHECK(string_->IsSeqOneByteString());
}
#if defined(V8_CC_MSVC)
#pragma warning(pop)
#endif
bool IsMatch(Object* string) override;
Handle<String> AsHandle(Isolate* isolate) override;
private:
Handle<SeqOneByteString> string_;
int from_;
int length_;
};
class TwoByteStringKey : public SequentialStringKey<uc16> {
public:
explicit TwoByteStringKey(Vector<const uc16> str, uint64_t seed)
: SequentialStringKey<uc16>(str, seed) {}
bool IsMatch(Object* string) override {
return String::cast(string)->IsTwoByteEqualTo(string_);
}
Handle<String> AsHandle(Isolate* isolate) override;
};
// Utf8StringKey carries a vector of chars as key.
class Utf8StringKey : public StringTableKey {
public:
explicit Utf8StringKey(Vector<const char> string, uint64_t seed)
: StringTableKey(StringHasher::ComputeUtf8Hash(string, seed, &chars_)),
string_(string) {}
bool IsMatch(Object* string) override {
return String::cast(string)->IsUtf8EqualTo(string_);
}
Handle<String> AsHandle(Isolate* isolate) override {
return isolate->factory()->NewInternalizedStringFromUtf8(string_, chars_,
HashField());
}
private:
Vector<const char> string_;
int chars_; // Caches the number of characters when computing the hash code.
};
bool String::Equals(String* other) {
if (other == this) return true;
if (this->IsInternalizedString() && other->IsInternalizedString()) {
return false;
}
return SlowEquals(other);
}
bool String::Equals(Isolate* isolate, Handle<String> one, Handle<String> two) {
if (one.is_identical_to(two)) return true;
if (one->IsInternalizedString() && two->IsInternalizedString()) {
return false;
}
return SlowEquals(isolate, one, two);
}
Handle<String> String::Flatten(Isolate* isolate, Handle<String> string,
PretenureFlag pretenure) {
if (string->IsConsString()) {
Handle<ConsString> cons = Handle<ConsString>::cast(string);
if (cons->IsFlat()) {
string = handle(cons->first(), isolate);
} else {
return SlowFlatten(isolate, cons, pretenure);
}
}
if (string->IsThinString()) {
string = handle(Handle<ThinString>::cast(string)->actual(), isolate);
DCHECK(!string->IsConsString());
}
return string;
}
uint16_t String::Get(int index) {
DCHECK(index >= 0 && index < length());
switch (StringShape(this).full_representation_tag()) {
case kSeqStringTag | kOneByteStringTag:
return SeqOneByteString::cast(this)->SeqOneByteStringGet(index);
case kSeqStringTag | kTwoByteStringTag:
return SeqTwoByteString::cast(this)->SeqTwoByteStringGet(index);
case kConsStringTag | kOneByteStringTag:
case kConsStringTag | kTwoByteStringTag:
return ConsString::cast(this)->ConsStringGet(index);
case kExternalStringTag | kOneByteStringTag:
return ExternalOneByteString::cast(this)->ExternalOneByteStringGet(index);
case kExternalStringTag | kTwoByteStringTag:
return ExternalTwoByteString::cast(this)->ExternalTwoByteStringGet(index);
case kSlicedStringTag | kOneByteStringTag:
case kSlicedStringTag | kTwoByteStringTag:
return SlicedString::cast(this)->SlicedStringGet(index);
case kThinStringTag | kOneByteStringTag:
case kThinStringTag | kTwoByteStringTag:
return ThinString::cast(this)->ThinStringGet(index);
default:
break;
}
UNREACHABLE();
}
void String::Set(int index, uint16_t value) {
DCHECK(index >= 0 && index < length());
DCHECK(StringShape(this).IsSequential());
return this->IsOneByteRepresentation()
? SeqOneByteString::cast(this)->SeqOneByteStringSet(index, value)
: SeqTwoByteString::cast(this)->SeqTwoByteStringSet(index, value);
}
bool String::IsFlat() {
if (!StringShape(this).IsCons()) return true;
return ConsString::cast(this)->second()->length() == 0;
}
String* String::GetUnderlying() {
// Giving direct access to underlying string only makes sense if the
// wrapping string is already flattened.
DCHECK(this->IsFlat());
DCHECK(StringShape(this).IsIndirect());
STATIC_ASSERT(ConsString::kFirstOffset == SlicedString::kParentOffset);
STATIC_ASSERT(ConsString::kFirstOffset == ThinString::kActualOffset);
const int kUnderlyingOffset = SlicedString::kParentOffset;
return String::cast(READ_FIELD(this, kUnderlyingOffset));
}
template <class Visitor>
ConsString* String::VisitFlat(Visitor* visitor, String* string,
const int offset) {
int slice_offset = offset;
const int length = string->length();
DCHECK(offset <= length);
while (true) {
int32_t type = string->map()->instance_type();
switch (type & (kStringRepresentationMask | kStringEncodingMask)) {
case kSeqStringTag | kOneByteStringTag:
visitor->VisitOneByteString(
SeqOneByteString::cast(string)->GetChars() + slice_offset,
length - offset);
return nullptr;
case kSeqStringTag | kTwoByteStringTag:
visitor->VisitTwoByteString(
SeqTwoByteString::cast(string)->GetChars() + slice_offset,
length - offset);
return nullptr;
case kExternalStringTag | kOneByteStringTag:
visitor->VisitOneByteString(
ExternalOneByteString::cast(string)->GetChars() + slice_offset,
length - offset);
return nullptr;
case kExternalStringTag | kTwoByteStringTag:
visitor->VisitTwoByteString(
ExternalTwoByteString::cast(string)->GetChars() + slice_offset,
length - offset);
return nullptr;
case kSlicedStringTag | kOneByteStringTag:
case kSlicedStringTag | kTwoByteStringTag: {
SlicedString* slicedString = SlicedString::cast(string);
slice_offset += slicedString->offset();
string = slicedString->parent();
continue;
}
case kConsStringTag | kOneByteStringTag:
case kConsStringTag | kTwoByteStringTag:
return ConsString::cast(string);
case kThinStringTag | kOneByteStringTag:
case kThinStringTag | kTwoByteStringTag:
string = ThinString::cast(string)->actual();
continue;
default:
UNREACHABLE();
}
}
}
template <>
inline Vector<const uint8_t> String::GetCharVector() {
String::FlatContent flat = GetFlatContent();
DCHECK(flat.IsOneByte());
return flat.ToOneByteVector();
}
template <>
inline Vector<const uc16> String::GetCharVector() {
String::FlatContent flat = GetFlatContent();
DCHECK(flat.IsTwoByte());
return flat.ToUC16Vector();
}
uint32_t String::ToValidIndex(Object* number) {
uint32_t index = PositiveNumberToUint32(number);
uint32_t length_value = static_cast<uint32_t>(length());
if (index > length_value) return length_value;
return index;
}
uint16_t SeqOneByteString::SeqOneByteStringGet(int index) {
DCHECK(index >= 0 && index < length());
return READ_BYTE_FIELD(this, kHeaderSize + index * kCharSize);
}
void SeqOneByteString::SeqOneByteStringSet(int index, uint16_t value) {
DCHECK(index >= 0 && index < length() && value <= kMaxOneByteCharCode);
WRITE_BYTE_FIELD(this, kHeaderSize + index * kCharSize,
static_cast<byte>(value));
}
Address SeqOneByteString::GetCharsAddress() {
return FIELD_ADDR(this, kHeaderSize);
}
uint8_t* SeqOneByteString::GetChars() {
return reinterpret_cast<uint8_t*>(GetCharsAddress());
}
Address SeqTwoByteString::GetCharsAddress() {
return FIELD_ADDR(this, kHeaderSize);
}
uc16* SeqTwoByteString::GetChars() {
return reinterpret_cast<uc16*>(FIELD_ADDR(this, kHeaderSize));
}
uint16_t SeqTwoByteString::SeqTwoByteStringGet(int index) {
DCHECK(index >= 0 && index < length());
return READ_UINT16_FIELD(this, kHeaderSize + index * kShortSize);
}
void SeqTwoByteString::SeqTwoByteStringSet(int index, uint16_t value) {
DCHECK(index >= 0 && index < length());
WRITE_UINT16_FIELD(this, kHeaderSize + index * kShortSize, value);
}
int SeqTwoByteString::SeqTwoByteStringSize(InstanceType instance_type) {
return SizeFor(length());
}
int SeqOneByteString::SeqOneByteStringSize(InstanceType instance_type) {
return SizeFor(length());
}
String* SlicedString::parent() {
return String::cast(READ_FIELD(this, kParentOffset));
}
void SlicedString::set_parent(Isolate* isolate, String* parent,
WriteBarrierMode mode) {
DCHECK(parent->IsSeqString() || parent->IsExternalString());
WRITE_FIELD(this, kParentOffset, parent);
CONDITIONAL_WRITE_BARRIER(this, kParentOffset, parent, mode);
}
SMI_ACCESSORS(SlicedString, offset, kOffsetOffset)
String* ConsString::first() {
return String::cast(READ_FIELD(this, kFirstOffset));
}
Object* ConsString::unchecked_first() { return READ_FIELD(this, kFirstOffset); }
void ConsString::set_first(Isolate* isolate, String* value,
WriteBarrierMode mode) {
WRITE_FIELD(this, kFirstOffset, value);
CONDITIONAL_WRITE_BARRIER(this, kFirstOffset, value, mode);
}
String* ConsString::second() {
return String::cast(READ_FIELD(this, kSecondOffset));
}
Object* ConsString::unchecked_second() {
return RELAXED_READ_FIELD(this, kSecondOffset);
}
void ConsString::set_second(Isolate* isolate, String* value,
WriteBarrierMode mode) {
WRITE_FIELD(this, kSecondOffset, value);
CONDITIONAL_WRITE_BARRIER(this, kSecondOffset, value, mode);
}
ACCESSORS(ThinString, actual, String, kActualOffset);
HeapObject* ThinString::unchecked_actual() const {
return reinterpret_cast<HeapObject*>(READ_FIELD(this, kActualOffset));
}
bool ExternalString::is_short() const {
InstanceType type = map()->instance_type();
return (type & kShortExternalStringMask) == kShortExternalStringTag;
}
Address ExternalString::resource_as_address() {
return *reinterpret_cast<Address*>(FIELD_ADDR(this, kResourceOffset));
}
void ExternalString::set_address_as_resource(Address address) {
DCHECK(IsAligned(address, kPointerSize));
*reinterpret_cast<Address*>(FIELD_ADDR(this, kResourceOffset)) = address;
if (IsExternalOneByteString()) {
ExternalOneByteString::cast(this)->update_data_cache();
} else {
ExternalTwoByteString::cast(this)->update_data_cache();
}
}
uint32_t ExternalString::resource_as_uint32() {
return static_cast<uint32_t>(
*reinterpret_cast<uintptr_t*>(FIELD_ADDR(this, kResourceOffset)));
}
void ExternalString::set_uint32_as_resource(uint32_t value) {
*reinterpret_cast<uintptr_t*>(FIELD_ADDR(this, kResourceOffset)) = value;
if (is_short()) return;
const char** data_field =
reinterpret_cast<const char**>(FIELD_ADDR(this, kResourceDataOffset));
*data_field = nullptr;
}
const ExternalOneByteString::Resource* ExternalOneByteString::resource() {
return *reinterpret_cast<Resource**>(FIELD_ADDR(this, kResourceOffset));
}
void ExternalOneByteString::update_data_cache() {
if (is_short()) return;
const char** data_field =
reinterpret_cast<const char**>(FIELD_ADDR(this, kResourceDataOffset));
*data_field = resource()->data();
}
void ExternalOneByteString::SetResource(
Isolate* isolate, const ExternalOneByteString::Resource* resource) {
set_resource(resource);
size_t new_payload = resource == nullptr ? 0 : resource->length();
if (new_payload > 0)
isolate->heap()->UpdateExternalString(this, 0, new_payload);
}
void ExternalOneByteString::set_resource(
const ExternalOneByteString::Resource* resource) {
DCHECK(IsAligned(reinterpret_cast<intptr_t>(resource), kPointerSize));
*reinterpret_cast<const Resource**>(FIELD_ADDR(this, kResourceOffset)) =
resource;
if (resource != nullptr) update_data_cache();
}
const uint8_t* ExternalOneByteString::GetChars() {
return reinterpret_cast<const uint8_t*>(resource()->data());
}
uint16_t ExternalOneByteString::ExternalOneByteStringGet(int index) {
DCHECK(index >= 0 && index < length());
return GetChars()[index];
}
const ExternalTwoByteString::Resource* ExternalTwoByteString::resource() {
return *reinterpret_cast<Resource**>(FIELD_ADDR(this, kResourceOffset));
}
void ExternalTwoByteString::update_data_cache() {
if (is_short()) return;
const uint16_t** data_field =
reinterpret_cast<const uint16_t**>(FIELD_ADDR(this, kResourceDataOffset));
*data_field = resource()->data();
}
void ExternalTwoByteString::SetResource(
Isolate* isolate, const ExternalTwoByteString::Resource* resource) {
set_resource(resource);
size_t new_payload = resource == nullptr ? 0 : resource->length() * 2;
if (new_payload > 0)
isolate->heap()->UpdateExternalString(this, 0, new_payload);
}
void ExternalTwoByteString::set_resource(
const ExternalTwoByteString::Resource* resource) {
*reinterpret_cast<const Resource**>(FIELD_ADDR(this, kResourceOffset)) =
resource;
if (resource != nullptr) update_data_cache();
}
const uint16_t* ExternalTwoByteString::GetChars() { return resource()->data(); }
uint16_t ExternalTwoByteString::ExternalTwoByteStringGet(int index) {
DCHECK(index >= 0 && index < length());
return GetChars()[index];
}
const uint16_t* ExternalTwoByteString::ExternalTwoByteStringGetData(
unsigned start) {
return GetChars() + start;
}
int ConsStringIterator::OffsetForDepth(int depth) { return depth & kDepthMask; }
void ConsStringIterator::PushLeft(ConsString* string) {
frames_[depth_++ & kDepthMask] = string;
}
void ConsStringIterator::PushRight(ConsString* string) {
// Inplace update.
frames_[(depth_ - 1) & kDepthMask] = string;
}
void ConsStringIterator::AdjustMaximumDepth() {
if (depth_ > maximum_depth_) maximum_depth_ = depth_;
}
void ConsStringIterator::Pop() {
DCHECK_GT(depth_, 0);
DCHECK(depth_ <= maximum_depth_);
depth_--;
}
uint16_t StringCharacterStream::GetNext() {
DCHECK(buffer8_ != nullptr && end_ != nullptr);
// Advance cursor if needed.
if (buffer8_ == end_) HasMore();
DCHECK(buffer8_ < end_);
return is_one_byte_ ? *buffer8_++ : *buffer16_++;
}
StringCharacterStream::StringCharacterStream(String* string, int offset)
: is_one_byte_(false) {
Reset(string, offset);
}
void StringCharacterStream::Reset(String* string, int offset) {
buffer8_ = nullptr;
end_ = nullptr;
ConsString* cons_string = String::VisitFlat(this, string, offset);
iter_.Reset(cons_string, offset);
if (cons_string != nullptr) {
string = iter_.Next(&offset);
if (string != nullptr) String::VisitFlat(this, string, offset);
}
}
bool StringCharacterStream::HasMore() {
if (buffer8_ != end_) return true;
int offset;
String* string = iter_.Next(&offset);
DCHECK_EQ(offset, 0);
if (string == nullptr) return false;
String::VisitFlat(this, string);
DCHECK(buffer8_ != end_);
return true;
}
void StringCharacterStream::VisitOneByteString(const uint8_t* chars,
int length) {
is_one_byte_ = true;
buffer8_ = chars;
end_ = chars + length;
}
void StringCharacterStream::VisitTwoByteString(const uint16_t* chars,
int length) {
is_one_byte_ = false;
buffer16_ = chars;
end_ = reinterpret_cast<const uint8_t*>(chars + length);
}
bool String::AsArrayIndex(uint32_t* index) {
uint32_t field = hash_field();
if (IsHashFieldComputed(field) && (field & kIsNotArrayIndexMask)) {
return false;
}
return SlowAsArrayIndex(index);
}
String::SubStringRange::SubStringRange(String* string, int first, int length)
: string_(string),
first_(first),
length_(length == -1 ? string->length() : length) {}
class String::SubStringRange::iterator final {
public:
typedef std::forward_iterator_tag iterator_category;
typedef int difference_type;
typedef uc16 value_type;
typedef uc16* pointer;
typedef uc16& reference;
iterator(const iterator& other)
: content_(other.content_), offset_(other.offset_) {}
uc16 operator*() { return content_.Get(offset_); }
bool operator==(const iterator& other) const {
return content_.UsesSameString(other.content_) && offset_ == other.offset_;
}
bool operator!=(const iterator& other) const {
return !content_.UsesSameString(other.content_) || offset_ != other.offset_;
}
iterator& operator++() {
++offset_;
return *this;
}
iterator operator++(int);
private:
friend class String;
iterator(String* from, int offset)
: content_(from->GetFlatContent()), offset_(offset) {}
String::FlatContent content_;
int offset_;
};
String::SubStringRange::iterator String::SubStringRange::begin() {
return String::SubStringRange::iterator(string_, first_);
}
String::SubStringRange::iterator String::SubStringRange::end() {
return String::SubStringRange::iterator(string_, first_ + length_);
}
} // namespace internal
} // namespace v8
#include "src/objects/object-macros-undef.h"
#endif // V8_OBJECTS_STRING_INL_H_
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