Files
Daniel Lemire e252a21f65 removing expand workaround (#2431)
* removing expland workaround

* minor fixes
2025-09-03 13:30:35 -04:00

656 lines
22 KiB
C++

/**
* This file is part of the builder API. It is temporarily in the ondemand
* directory but we will move it to a builder directory later.
*/
#include <array>
#include <cstring>
#include <type_traits>
#ifndef SIMDJSON_GENERIC_STRING_BUILDER_INL_H
#ifndef SIMDJSON_CONDITIONAL_INCLUDE
#define SIMDJSON_GENERIC_STRING_BUILDER_INL_H
#include "simdjson/generic/builder/json_string_builder.h"
#endif // SIMDJSON_CONDITIONAL_INCLUDE
/*
* Empirically, we have found that an inlined optimization is important for
* performance. The following macros are not ideal. We should find a better
* way to inline the code.
*/
#if defined(__SSE2__) || defined(__x86_64__) || defined(__x86_64) || \
(defined(_M_AMD64) || defined(_M_X64) || \
(defined(_M_IX86_FP) && _M_IX86_FP == 2))
#ifndef SIMDJSON_EXPERIMENTAL_HAS_SSE2
#define SIMDJSON_EXPERIMENTAL_HAS_SSE2 1
#endif
#endif
#if defined(__aarch64__) || defined(_M_ARM64)
#ifndef SIMDJSON_EXPERIMENTAL_HAS_NEON
#define SIMDJSON_EXPERIMENTAL_HAS_NEON 1
#endif
#endif
#if SIMDJSON_EXPERIMENTAL_HAS_NEON
#include <arm_neon.h>
#endif
#if SIMDJSON_EXPERIMENTAL_HAS_SSE2
#include <emmintrin.h>
#endif
namespace simdjson {
namespace SIMDJSON_IMPLEMENTATION {
namespace builder {
static SIMDJSON_CONSTEXPR_LAMBDA std::array<uint8_t, 256> json_quotable_character = {
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
/**
A possible SWAR implementation of has_json_escapable_byte. It is not used because
it is slower than the current implementation. It is kept here for reference (to show
that we tried it).
inline bool has_json_escapable_byte(uint64_t x) {
uint64_t is_ascii = 0x8080808080808080ULL & ~x;
uint64_t xor2 = x ^ 0x0202020202020202ULL;
uint64_t lt32_or_eq34 = xor2 - 0x2121212121212121ULL;
uint64_t sub92 = x ^ 0x5C5C5C5C5C5C5C5CULL;
uint64_t eq92 = (sub92 - 0x0101010101010101ULL);
return ((lt32_or_eq34 | eq92) & is_ascii) != 0;
}
**/
SIMDJSON_CONSTEXPR_LAMBDA simdjson_inline bool
simple_needs_escaping(std::string_view v) {
for (char c : v) {
// a table lookup is faster than a series of comparisons
if(json_quotable_character[static_cast<uint8_t>(c)]) {
return true;
}
}
return false;
}
#if SIMDJSON_EXPERIMENTAL_HAS_NEON
simdjson_inline bool fast_needs_escaping(std::string_view view) {
if (view.size() < 16) {
return simple_needs_escaping(view);
}
size_t i = 0;
uint8x16_t running = vdupq_n_u8(0);
uint8x16_t v34 = vdupq_n_u8(34);
uint8x16_t v92 = vdupq_n_u8(92);
for (; i + 15 < view.size(); i += 16) {
uint8x16_t word = vld1q_u8((const uint8_t *)view.data() + i);
running = vorrq_u8(running, vceqq_u8(word, v34));
running = vorrq_u8(running, vceqq_u8(word, v92));
running = vorrq_u8(running, vcltq_u8(word, vdupq_n_u8(32)));
}
if (i < view.size()) {
uint8x16_t word =
vld1q_u8((const uint8_t *)view.data() + view.length() - 16);
running = vorrq_u8(running, vceqq_u8(word, v34));
running = vorrq_u8(running, vceqq_u8(word, v92));
running = vorrq_u8(running, vcltq_u8(word, vdupq_n_u8(32)));
}
return vmaxvq_u32(vreinterpretq_u32_u8(running)) != 0;
}
#elif SIMDJSON_EXPERIMENTAL_HAS_SSE2
simdjson_inline bool fast_needs_escaping(std::string_view view) {
if (view.size() < 16) {
return simple_needs_escaping(view);
}
size_t i = 0;
__m128i running = _mm_setzero_si128();
for (; i + 15 < view.size(); i += 16) {
__m128i word = _mm_loadu_si128(reinterpret_cast<const __m128i *>(view.data() + i));
running = _mm_or_si128(running, _mm_cmpeq_epi8(word, _mm_set1_epi8(34)));
running = _mm_or_si128(running, _mm_cmpeq_epi8(word, _mm_set1_epi8(92)));
running = _mm_or_si128(
running, _mm_cmpeq_epi8(_mm_subs_epu8(word, _mm_set1_epi8(31)),
_mm_setzero_si128()));
}
if (i < view.size()) {
__m128i word =
_mm_loadu_si128(reinterpret_cast<const __m128i *>(view.data() + view.length() - 16));
running = _mm_or_si128(running, _mm_cmpeq_epi8(word, _mm_set1_epi8(34)));
running = _mm_or_si128(running, _mm_cmpeq_epi8(word, _mm_set1_epi8(92)));
running = _mm_or_si128(
running, _mm_cmpeq_epi8(_mm_subs_epu8(word, _mm_set1_epi8(31)),
_mm_setzero_si128()));
}
return _mm_movemask_epi8(running) != 0;
}
#else
simdjson_inline bool fast_needs_escaping(std::string_view view) {
return simple_needs_escaping(view);
}
#endif
SIMDJSON_CONSTEXPR_LAMBDA inline size_t
find_next_json_quotable_character(const std::string_view view,
size_t location) noexcept {
for (auto pos = view.begin() + location; pos != view.end(); ++pos) {
if (json_quotable_character[static_cast<uint8_t>(*pos)]) {
return pos - view.begin();
}
}
return size_t(view.size());
}
SIMDJSON_CONSTEXPR_LAMBDA static std::string_view control_chars[] = {
"\\u0000", "\\u0001", "\\u0002", "\\u0003", "\\u0004", "\\u0005", "\\u0006",
"\\u0007", "\\b", "\\t", "\\n", "\\u000b", "\\f", "\\r",
"\\u000e", "\\u000f", "\\u0010", "\\u0011", "\\u0012", "\\u0013", "\\u0014",
"\\u0015", "\\u0016", "\\u0017", "\\u0018", "\\u0019", "\\u001a", "\\u001b",
"\\u001c", "\\u001d", "\\u001e", "\\u001f"};
// All Unicode characters may be placed within the quotation marks, except for the
// characters that MUST be escaped: quotation mark, reverse solidus, and the control
// characters (U+0000 through U+001F).
// There are two-character sequence escape representations of some popular characters:
// \", \\, \b, \f, \n, \r, \t.
SIMDJSON_CONSTEXPR_LAMBDA void escape_json_char(char c, char *&out) {
if (c == '"') {
memcpy(out, "\\\"", 2);
out += 2;
} else if (c == '\\') {
memcpy(out, "\\\\", 2);
out += 2;
} else {
std::string_view v = control_chars[uint8_t(c)];
memcpy(out, v.data(), v.size());
out += v.size();
}
}
inline size_t write_string_escaped(const std::string_view input, char *out) {
size_t mysize = input.size();
if (!fast_needs_escaping(input)) { // fast path!
memcpy(out, input.data(), input.size());
return input.size();
}
const char *const initout = out;
size_t location = find_next_json_quotable_character(input, 0);
memcpy(out, input.data(), location);
out += location;
escape_json_char(input[location], out);
location += 1;
while (location < mysize) {
size_t newlocation = find_next_json_quotable_character(input, location);
memcpy(out, input.data() + location, newlocation - location);
out += newlocation - location;
location = newlocation;
if (location == mysize) {
break;
}
escape_json_char(input[location], out);
location += 1;
}
return out - initout;
}
simdjson_inline string_builder::string_builder(size_t initial_capacity)
: buffer(new(std::nothrow) char[initial_capacity]), position(0),
capacity(buffer.get() != nullptr ? initial_capacity : 0),
is_valid(buffer.get() != nullptr) {}
simdjson_inline bool string_builder::capacity_check(size_t upcoming_bytes) {
// We use the convention that when is_valid is false, then the capacity and
// the position are 0.
// Most of the time, this function will return true.
if (simdjson_likely(upcoming_bytes <= capacity - position)) {
return true;
}
// check for overflow, most of the time there is no overflow
if (simdjson_likely(position + upcoming_bytes < position)) {
return false;
}
// We will rarely get here.
grow_buffer((std::max)(capacity * 2, position + upcoming_bytes));
// If the buffer allocation failed, we set is_valid to false.
return is_valid;
}
simdjson_inline void string_builder::grow_buffer(size_t desired_capacity) {
if (!is_valid) {
return;
}
std::unique_ptr<char[]> new_buffer(new (std::nothrow) char[desired_capacity]);
if (new_buffer.get() == nullptr) {
set_valid(false);
return;
}
std::memcpy(new_buffer.get(), buffer.get(), position);
buffer.swap(new_buffer);
capacity = desired_capacity;
}
simdjson_inline void string_builder::set_valid(bool valid) noexcept {
if (!valid) {
is_valid = false;
capacity = 0;
position = 0;
buffer.reset();
} else {
is_valid = true;
}
}
simdjson_inline size_t string_builder::size() const noexcept {
return position;
}
simdjson_inline void string_builder::append(char c) noexcept {
if (capacity_check(1)) {
buffer.get()[position++] = c;
}
}
simdjson_inline void string_builder::append_null() noexcept {
constexpr char null_literal[] = "null";
constexpr size_t null_len = sizeof(null_literal) - 1;
if (capacity_check(null_len)) {
std::memcpy(buffer.get() + position, null_literal, null_len);
position += null_len;
}
}
simdjson_inline void string_builder::clear() noexcept {
position = 0;
// if it was invalid, we should try to repair it
if (!is_valid) {
capacity = 0;
buffer.reset();
is_valid = true;
}
}
namespace internal {
// We could specialize further for 32-bit integers.
simdjson_really_inline int int_log2(uint32_t x) { return (63 - leading_zeroes(x | 1)); }
simdjson_really_inline int fast_digit_count(uint32_t x) {
static uint64_t table[] = {
4294967296, 8589934582, 8589934582, 8589934582, 12884901788,
12884901788, 12884901788, 17179868184, 17179868184, 17179868184,
21474826480, 21474826480, 21474826480, 21474826480, 25769703776,
25769703776, 25769703776, 30063771072, 30063771072, 30063771072,
34349738368, 34349738368, 34349738368, 34349738368, 38554705664,
38554705664, 38554705664, 41949672960, 41949672960, 41949672960,
42949672960, 42949672960};
return uint32_t((x + table[int_log2(x)]) >> 32);
}
simdjson_really_inline int int_log2(uint64_t x) { return 63 - leading_zeroes(x | 1); }
simdjson_really_inline int fast_digit_count(uint64_t x) {
static uint64_t table[] = {9,
99,
999,
9999,
99999,
999999,
9999999,
99999999,
999999999,
9999999999,
99999999999,
999999999999,
9999999999999,
99999999999999,
999999999999999ULL,
9999999999999999ULL,
99999999999999999ULL,
999999999999999999ULL,
9999999999999999999ULL};
int y = (19 * int_log2(x) >> 6);
y += x > table[y];
return y + 1;
}
template <typename number_type, typename = typename std::enable_if<
std::is_unsigned<number_type>::value>::type>
simdjson_really_inline size_t digit_count(number_type v) noexcept {
static_assert(sizeof(number_type) == 8 || sizeof(number_type) == 4 ||
sizeof(number_type) == 2 || sizeof(number_type) == 1,
"We only support 8-bit, 16-bit, 32-bit and 64-bit numbers");
return fast_digit_count(v);
}
static const char decimal_table[200] = {
0x30, 0x30, 0x30, 0x31, 0x30, 0x32, 0x30, 0x33, 0x30, 0x34, 0x30, 0x35,
0x30, 0x36, 0x30, 0x37, 0x30, 0x38, 0x30, 0x39, 0x31, 0x30, 0x31, 0x31,
0x31, 0x32, 0x31, 0x33, 0x31, 0x34, 0x31, 0x35, 0x31, 0x36, 0x31, 0x37,
0x31, 0x38, 0x31, 0x39, 0x32, 0x30, 0x32, 0x31, 0x32, 0x32, 0x32, 0x33,
0x32, 0x34, 0x32, 0x35, 0x32, 0x36, 0x32, 0x37, 0x32, 0x38, 0x32, 0x39,
0x33, 0x30, 0x33, 0x31, 0x33, 0x32, 0x33, 0x33, 0x33, 0x34, 0x33, 0x35,
0x33, 0x36, 0x33, 0x37, 0x33, 0x38, 0x33, 0x39, 0x34, 0x30, 0x34, 0x31,
0x34, 0x32, 0x34, 0x33, 0x34, 0x34, 0x34, 0x35, 0x34, 0x36, 0x34, 0x37,
0x34, 0x38, 0x34, 0x39, 0x35, 0x30, 0x35, 0x31, 0x35, 0x32, 0x35, 0x33,
0x35, 0x34, 0x35, 0x35, 0x35, 0x36, 0x35, 0x37, 0x35, 0x38, 0x35, 0x39,
0x36, 0x30, 0x36, 0x31, 0x36, 0x32, 0x36, 0x33, 0x36, 0x34, 0x36, 0x35,
0x36, 0x36, 0x36, 0x37, 0x36, 0x38, 0x36, 0x39, 0x37, 0x30, 0x37, 0x31,
0x37, 0x32, 0x37, 0x33, 0x37, 0x34, 0x37, 0x35, 0x37, 0x36, 0x37, 0x37,
0x37, 0x38, 0x37, 0x39, 0x38, 0x30, 0x38, 0x31, 0x38, 0x32, 0x38, 0x33,
0x38, 0x34, 0x38, 0x35, 0x38, 0x36, 0x38, 0x37, 0x38, 0x38, 0x38, 0x39,
0x39, 0x30, 0x39, 0x31, 0x39, 0x32, 0x39, 0x33, 0x39, 0x34, 0x39, 0x35,
0x39, 0x36, 0x39, 0x37, 0x39, 0x38, 0x39, 0x39,
};
} // namespace internal
template <typename number_type, typename>
simdjson_inline void string_builder::append(number_type v) noexcept {
static_assert(std::is_same<number_type, bool>::value ||
std::is_integral<number_type>::value ||
std::is_floating_point<number_type>::value,
"Unsupported number type");
// If C++17 is available, we can 'if constexpr' here.
SIMDJSON_IF_CONSTEXPR(std::is_same<number_type, bool>::value) {
if (v) {
constexpr char true_literal[] = "true";
constexpr size_t true_len = sizeof(true_literal) - 1;
if (capacity_check(true_len)) {
std::memcpy(buffer.get() + position, true_literal, true_len);
position += true_len;
}
} else {
constexpr char false_literal[] = "false";
constexpr size_t false_len = sizeof(false_literal) - 1;
if (capacity_check(false_len)) {
std::memcpy(buffer.get() + position, false_literal, false_len);
position += false_len;
}
}
}
else SIMDJSON_IF_CONSTEXPR(std::is_unsigned<number_type>::value) {
constexpr size_t max_number_size = 20;
if (capacity_check(max_number_size)) {
using unsigned_type = typename std::make_unsigned<number_type>::type;
unsigned_type pv = static_cast<unsigned_type>(v);
size_t dc = internal::digit_count(pv);
char *write_pointer = buffer.get() + position + dc - 1;
while (pv >= 100) {
memcpy(write_pointer - 1, &internal::decimal_table[(pv % 100)*2], 2);
write_pointer -= 2;
pv /= 100;
}
if (pv >= 10) {
*write_pointer-- = char('0' + (pv % 10));
pv /= 10;
}
*write_pointer = char('0' + pv);
position += dc;
}
}
else SIMDJSON_IF_CONSTEXPR(std::is_integral<number_type>::value) {
constexpr size_t max_number_size = 20;
if (capacity_check(max_number_size)) {
using unsigned_type = typename std::make_unsigned<number_type>::type;
bool negative = v < 0;
unsigned_type pv = static_cast<unsigned_type>(v);
if (negative) {
pv = 0 - pv; // the 0 is for Microsoft
}
size_t dc = internal::digit_count(pv);
if (negative) {
buffer.get()[position++] = '-';
}
char *write_pointer = buffer.get() + position + dc - 1;
while (pv >= 100) {
memcpy(write_pointer - 1, &internal::decimal_table[(pv % 100)*2], 2);
write_pointer -= 2;
pv /= 100;
}
if (pv >= 10) {
*write_pointer-- = char('0' + (pv % 10));
pv /= 10;
}
*write_pointer = char('0' + pv);
position += dc;
}
}
else SIMDJSON_IF_CONSTEXPR(std::is_floating_point<number_type>::value) {
constexpr size_t max_number_size = 24;
if (capacity_check(max_number_size)) {
// We could specialize for float.
char *end = simdjson::internal::to_chars(buffer.get() + position, nullptr,
double(v));
position = end - buffer.get();
}
}
}
simdjson_inline void
string_builder::escape_and_append(std::string_view input) noexcept {
// escaping might turn a control character into \x00xx so 6 characters.
if (capacity_check(6 * input.size())) {
position += write_string_escaped(input, buffer.get() + position);
}
}
simdjson_inline void
string_builder::escape_and_append_with_quotes(std::string_view input) noexcept {
// escaping might turn a control character into \x00xx so 6 characters.
if (capacity_check(2 + 6 * input.size())) {
buffer.get()[position++] = '"';
position += write_string_escaped(input, buffer.get() + position);
buffer.get()[position++] = '"';
}
}
simdjson_inline void
string_builder::escape_and_append_with_quotes(char input) noexcept {
// escaping might turn a control character into \x00xx so 6 characters.
if (capacity_check(2 + 6 * 1)) {
buffer.get()[position++] = '"';
std::string_view cinput(&input, 1);
position += write_string_escaped(cinput, buffer.get() + position);
buffer.get()[position++] = '"';
}
}
simdjson_inline void string_builder::escape_and_append_with_quotes(const char* input) noexcept {
std::string_view cinput(input);
escape_and_append_with_quotes(cinput);
}
simdjson_inline void string_builder::append_raw(const char *c) noexcept {
size_t len = std::strlen(c);
append_raw(c, len);
}
simdjson_inline void
string_builder::append_raw(std::string_view input) noexcept {
if (capacity_check(input.size())) {
std::memcpy(buffer.get() + position, input.data(), input.size());
position += input.size();
}
}
simdjson_inline void string_builder::append_raw(const char *str,
size_t len) noexcept {
if (capacity_check(len)) {
std::memcpy(buffer.get() + position, str, len);
position += len;
}
}
#if SIMDJSON_SUPPORTS_CONCEPTS
// Support for optional types (std::optional, etc.)
template <concepts::optional_type T>
simdjson_inline void string_builder::append(const T &opt) {
if (opt) {
append(*opt);
} else {
append_null();
}
}
template <typename T>
requires(std::is_convertible<T, std::string_view>::value ||
std::is_same<T, const char*>::value )
simdjson_inline void string_builder::append(const T &value) {
escape_and_append_with_quotes(value);
}
#endif
#if SIMDJSON_SUPPORTS_RANGES && SIMDJSON_SUPPORTS_CONCEPTS
// Support for range-based appending (std::ranges::view, etc.)
template <std::ranges::range R>
requires (!std::is_convertible<R, std::string_view>::value)
simdjson_inline void string_builder::append(const R &range) noexcept {
auto it = std::ranges::begin(range);
auto end = std::ranges::end(range);
if constexpr (concepts::is_pair<typename R::value_type>) {
start_object();
if (it == end) {
end_object();
return; // Handle empty range
}
// Append first item without leading comma
append_key_value(it->first, it->second);
++it;
// Append remaining items with preceding commas
for (; it != end; ++it) {
append_comma();
append_key_value(it->first, it->second);
}
end_object();
} else {
start_array();
if (it == end) {
end_array();
return; // Handle empty range
}
// Append first item without leading comma
append(*it);
++it;
// Append remaining items with preceding commas
for (; it != end; ++it) {
append_comma();
append(*it);
}
end_array();
}
}
#endif
#if SIMDJSON_EXCEPTIONS
simdjson_inline string_builder::operator std::string() const noexcept(false) {
return std::string(std::string_view());
}
simdjson_inline string_builder::operator std::string_view() const
noexcept(false) simdjson_lifetime_bound {
return view();
}
#endif
simdjson_inline simdjson_result<std::string_view>
string_builder::view() const noexcept {
if (!is_valid) {
return simdjson::OUT_OF_CAPACITY;
}
return std::string_view(buffer.get(), position);
}
simdjson_inline simdjson_result<const char *> string_builder::c_str() noexcept {
if (capacity_check(1)) {
buffer.get()[position] = '\0';
return buffer.get();
}
return simdjson::OUT_OF_CAPACITY;
}
simdjson_inline bool string_builder::validate_unicode() const noexcept {
return simdjson::validate_utf8(buffer.get(), position);
}
simdjson_inline void string_builder::start_object() noexcept {
if (capacity_check(1)) {
buffer.get()[position++] = '{';
}
}
simdjson_inline void string_builder::end_object() noexcept {
if (capacity_check(1)) {
buffer.get()[position++] = '}';
}
}
simdjson_inline void string_builder::start_array() noexcept {
if (capacity_check(1)) {
buffer.get()[position++] = '[';
}
}
simdjson_inline void string_builder::end_array() noexcept {
if (capacity_check(1)) {
buffer.get()[position++] = ']';
}
}
simdjson_inline void string_builder::append_comma() noexcept {
if (capacity_check(1)) {
buffer.get()[position++] = ',';
}
}
simdjson_inline void string_builder::append_colon() noexcept {
if (capacity_check(1)) {
buffer.get()[position++] = ':';
}
}
template<typename key_type, typename value_type>
simdjson_inline void string_builder::append_key_value(key_type key, value_type value) noexcept {
static_assert(
std::is_same<key_type, const char*>::value ||
std::is_convertible<key_type, std::string_view>::value,
"Unsupported key type");
escape_and_append_with_quotes(key);
append_colon();
SIMDJSON_IF_CONSTEXPR(std::is_same<value_type, std::nullptr_t>::value) {
append_null();
} else SIMDJSON_IF_CONSTEXPR(std::is_same<value_type, char>::value) {
escape_and_append_with_quotes(value);
} else SIMDJSON_IF_CONSTEXPR(std::is_convertible<value_type, std::string_view>::value) {
escape_and_append_with_quotes(value);
} else SIMDJSON_IF_CONSTEXPR(std::is_same<value_type, const char*>::value) {
escape_and_append_with_quotes(value);
} else {
append(value);
}
}
} // namespace builder
} // namespace SIMDJSON_IMPLEMENTATION
} // namespace simdjson
#endif // SIMDJSON_GENERIC_STRING_BUILDER_INL_H