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dependabot[bot] 976bbc4b64 build(deps): bump mkdocs-git-revision-date-localized-plugin
Bumps [mkdocs-git-revision-date-localized-plugin](https://github.com/timvink/mkdocs-git-revision-date-localized-plugin) from 1.6.2 to 1.6.3.
- [Release notes](https://github.com/timvink/mkdocs-git-revision-date-localized-plugin/releases)
- [Commits](https://github.com/timvink/mkdocs-git-revision-date-localized-plugin/compare/v1.6.2...v1.6.3)

---
updated-dependencies:
- dependency-name: mkdocs-git-revision-date-localized-plugin
  dependency-version: 1.6.3
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
2026-11-09 18:03:54 +00:00
Niels Lohmann 6f01030c4e docs: fix json_view links in the 3.13.0 performance blog post (#6044)
#6018 split features/json_view.md into features/json_view/ sub-pages while
#6022 added a blog post linking to the old page, so `mkdocs build --strict`
failed on develop (Publish documentation run 42577793091). Point the links
to json_view/index.md and json_view/editing.md.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-11-09 11:37:52 +01:00
6 changed files with 5 additions and 198 deletions

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@@ -22,7 +22,7 @@ Since 2016, the [README](https://github.com/nlohmann/json#readme) of this librar
That sentence is still true, but the gap is a lot smaller now. Swap the 3.12.0 header for the 3.13.0 one, recompile, and
the 182 benchmarks of the library's own suite run 3.0× as fast on an Apple M1 Max (geometric mean; 3.1× on an Intel
MacBook Pro from 2016). Not a line of your code changes. Parsing typical documents got 3.1–4.3× as fast, and writing
them 3.0–6.7×. The new version also adds [`json_document`](../../features/json_view.md), a second way to hold a parsed
them 3.0–6.7×. The new version also adds [`json_document`](../../features/json_view/index.md), a second way to hold a parsed
document, which competes with the fastest C++ and Rust JSON libraries; [How it compares](#how-it-compares) has the
numbers, including where it loses. The price is compile time: two small example programs take 34–62% longer to compile.
A precompiled header or a C++20 module wins back most or all of that in debug builds, and 41–91% of it in optimized
@@ -397,7 +397,7 @@ runs one word first. Inlining the vector code into the lexer cost 5% of validati
no string of that file is long enough to reach it: the scan function, which runs once per token, saved more registers
and needed a stack slot.
[`json_document`](../../features/json_view.md), the new document type of `json_view.hpp`, also skips the digits after a
[`json_document`](../../features/json_view/index.md), the new document type of `json_view.hpp`, also skips the digits after a
decimal point 16 bytes at a time with SSE2: a compare and a bit mask instead of a branch per digit, about 33% of the
instructions for a 12-digit fraction. Parsing `canada.json` got 22% faster on x86-64, a file of 10,000 floats 28–32%.
@@ -1132,7 +1132,7 @@ million small objects 1.39×.
After all of the above, [`json::parse()`](../../api/basic_json/parse.md) is still bound by what it builds: one heap
allocation per string, array and object, and a `std::map` node per member, all of which have to be freed again. Many
programs only parse a document, read some fields and throw it away, or change a few values and write it back. For them,
3.13.0 adds [`json_document`](../../features/json_view.md) and `json_view` in a new header, `<nlohmann/json_view.hpp>`.
3.13.0 adds [`json_document`](../../features/json_view/index.md) and `json_view` in a new header, `<nlohmann/json_view.hpp>`.
The two figures below show what each parser makes of this 54-byte text:
```json
@@ -1215,7 +1215,7 @@ static_assert(sizeof(node) == 16, "node must stay 16 bytes");
### It can be edited, too
A read-only index is the easy case, and a fair objection is that `json_document` is only fast because it can't change.
[`json_editable_document`](../../features/json_view.md#editing-a-document) has `set()`, `insert()`, `erase()` and
[`json_editable_document`](../../features/json_view/editing.md) has `set()`, `insert()`, `erase()` and
`push_back()`. An edit never writes into the source text and never moves the parsed index:
- a new scalar is written over its own node, with new string and number text in an append-only arena;
+1 -1
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@@ -1,7 +1,7 @@
wheel==0.48.0
mkdocs==1.6.1 # documentation framework
mkdocs-git-revision-date-localized-plugin==1.6.2 # plugin "git-revision-date-localized"
mkdocs-git-revision-date-localized-plugin==1.6.3 # plugin "git-revision-date-localized"
mkdocs-material==9.8.0 # theme for mkdocs
mkdocs-material-extensions==1.3.1 # extensions
mkdocs-minify-plugin==0.8.0 # plugin "minify"
@@ -1348,64 +1348,6 @@ struct iterator_input_adapter_factory<IteratorType, SentinelType, enable_if_t<is
}
};
/*!
@brief whether @a IteratorType is an iterator of std::string or of a
std::vector of 1-byte elements
Their elements are contiguous, but before C++20 that cannot be detected from
the iterator type (std::contiguous_iterator), so an iterator pair of them would
be read one character at a time through the iterators. They are read as the
pointer range they are instead, as the containers themselves are (see the
container overload of input_adapter()). The types are matched exactly, so no
other iterator can be mistaken for one. (std::basic_string is only matched for
char: other character types need std::char_traits specializations that the
standard library need not have.)
*/
template<typename CharType>
struct is_byte_char_type
{
// a member, not an integral_constant argument, which astyle misformats
static constexpr bool value = sizeof(CharType) == 1 && std::is_integral<CharType>::value && !std::is_same<CharType, bool>::value;
};
template<typename IteratorType, typename CharType, bool IsByte = is_byte_char_type<CharType>::value>
struct is_std_contiguous_byte_iterator_impl : std::false_type {};
// (the containers are only named for byte types)
template<typename IteratorType, typename CharType>
struct is_std_contiguous_byte_iterator_impl<IteratorType, CharType, true>
{
static constexpr bool value = !std::is_pointer<IteratorType>::value
&& (std::is_same<IteratorType, typename std::vector<CharType>::iterator>::value
|| std::is_same<IteratorType, typename std::vector<CharType>::const_iterator>::value
|| std::is_same<IteratorType, std::string::iterator>::value
|| std::is_same<IteratorType, std::string::const_iterator>::value);
};
template<typename IteratorType>
struct is_std_contiguous_byte_iterator
: is_std_contiguous_byte_iterator_impl<IteratorType, typename std::remove_cv<typename std::iterator_traits<IteratorType>::value_type>::type> {};
template<typename IteratorType>
struct iterator_input_adapter_factory<IteratorType, IteratorType, enable_if_t<is_std_contiguous_byte_iterator<IteratorType>::value>>
{
using iterator_type = IteratorType;
using sentinel_type = IteratorType;
using char_type = typename std::remove_cv<typename std::iterator_traits<iterator_type>::value_type>::type;
using adapter_type = iterator_input_adapter<const char_type*>;
static adapter_type create(IteratorType first, IteratorType last)
{
if (first == last)
{
// (an empty range must not be dereferenced)
return adapter_type(nullptr, nullptr);
}
const char_type* const begin = std::addressof(*first);
return adapter_type(begin, begin + (last - first));
}
};
// General purpose iterator-based input (iterator+sentinel pair; SentinelType
// defaults to IteratorType for the common same-type case, but may differ for
// C++20 ranges-style iterator+sentinel pairs). Only enable for types that can
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@@ -10457,64 +10457,6 @@ struct iterator_input_adapter_factory<IteratorType, SentinelType, enable_if_t<is
}
};
/*!
@brief whether @a IteratorType is an iterator of std::string or of a
std::vector of 1-byte elements
Their elements are contiguous, but before C++20 that cannot be detected from
the iterator type (std::contiguous_iterator), so an iterator pair of them would
be read one character at a time through the iterators. They are read as the
pointer range they are instead, as the containers themselves are (see the
container overload of input_adapter()). The types are matched exactly, so no
other iterator can be mistaken for one. (std::basic_string is only matched for
char: other character types need std::char_traits specializations that the
standard library need not have.)
*/
template<typename CharType>
struct is_byte_char_type
{
// a member, not an integral_constant argument, which astyle misformats
static constexpr bool value = sizeof(CharType) == 1 && std::is_integral<CharType>::value && !std::is_same<CharType, bool>::value;
};
template<typename IteratorType, typename CharType, bool IsByte = is_byte_char_type<CharType>::value>
struct is_std_contiguous_byte_iterator_impl : std::false_type {};
// (the containers are only named for byte types)
template<typename IteratorType, typename CharType>
struct is_std_contiguous_byte_iterator_impl<IteratorType, CharType, true>
{
static constexpr bool value = !std::is_pointer<IteratorType>::value
&& (std::is_same<IteratorType, typename std::vector<CharType>::iterator>::value
|| std::is_same<IteratorType, typename std::vector<CharType>::const_iterator>::value
|| std::is_same<IteratorType, std::string::iterator>::value
|| std::is_same<IteratorType, std::string::const_iterator>::value);
};
template<typename IteratorType>
struct is_std_contiguous_byte_iterator
: is_std_contiguous_byte_iterator_impl<IteratorType, typename std::remove_cv<typename std::iterator_traits<IteratorType>::value_type>::type> {};
template<typename IteratorType>
struct iterator_input_adapter_factory<IteratorType, IteratorType, enable_if_t<is_std_contiguous_byte_iterator<IteratorType>::value>>
{
using iterator_type = IteratorType;
using sentinel_type = IteratorType;
using char_type = typename std::remove_cv<typename std::iterator_traits<iterator_type>::value_type>::type;
using adapter_type = iterator_input_adapter<const char_type*>;
static adapter_type create(IteratorType first, IteratorType last)
{
if (first == last)
{
// (an empty range must not be dereferenced)
return adapter_type(nullptr, nullptr);
}
const char_type* const begin = std::addressof(*first);
return adapter_type(begin, begin + (last - first));
}
};
// General purpose iterator-based input (iterator+sentinel pair; SentinelType
// defaults to IteratorType for the common same-type case, but may differ for
// C++20 ranges-style iterator+sentinel pairs). Only enable for types that can
-2
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@@ -1674,8 +1674,6 @@ TEST_CASE("BSON input that cannot be read is discarded by every overload")
json _;
CHECK_THROWS_AS(_ = json::from_bson(input.begin(), input.end()), json::parse_error&);
CHECK(json::from_bson(input, true, false).is_discarded());
// false positive: Infer takes std::integral_constant<bool, false>::value for a pointer
// @infer-ignore NULLPTR_DEREFERENCE
CHECK(json::from_bson(input.begin(), input.end(), true, false).is_discarded());
#ifndef JSON_TEST_DEPRECATED_FUNCTIONS_DELETED
CHECK(json::from_bson(input.data(), input.size(), true, false).is_discarded());
-75
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@@ -32,7 +32,6 @@ using nlohmann::json;
#include <iostream>
#include <iterator>
#include <list>
#include <sstream>
#include <string>
#include <valarray>
@@ -1410,77 +1409,3 @@ TEST_CASE("indentation runs of every length around the 8-byte skip")
CHECK(parse_result(indented("[\n~1]", std::string(17, ' ')), true) == "[1]");
}
#endif
#if !defined(JSON_NOEXCEPTION)
namespace
{
/// the value of parsing [first, last), or the message of the exception
template<typename Iterator>
std::string outcome_of(Iterator first, Iterator last)
{
try
{
return json::parse(first, last).dump();
}
catch (const json::exception& e)
{
return e.what();
}
}
/// the bytes of @a text as a vector of @a T (explicit casts: no implicit char conversion)
template<typename T>
std::vector<T> bytes_as(const std::string& text)
{
std::vector<T> result;
result.reserve(text.size());
for (const char c : text)
{
result.push_back(static_cast<T>(c));
}
return result;
}
/// a std::string, std::vector<char>, <unsigned char> and <signed char> as
/// iterator pairs: the same as the byte path (std::list iterators)
void check_iterator_pairs(const std::string& text)
{
CAPTURE(text)
const std::list<char> bytes(text.begin(), text.end());
const std::string expected = outcome_of(bytes.begin(), bytes.end());
const bool expected_accept = json::accept(bytes.begin(), bytes.end());
std::string s = text;
CHECK(outcome_of(s.begin(), s.end()) == expected);
CHECK(outcome_of(s.cbegin(), s.cend()) == expected);
CHECK(json::accept(s.cbegin(), s.cend()) == expected_accept);
const std::vector<char> vc(text.begin(), text.end());
CHECK(outcome_of(vc.begin(), vc.end()) == expected);
const std::vector<unsigned char> vu = bytes_as<unsigned char>(text);
CHECK(outcome_of(vu.begin(), vu.end()) == expected);
CHECK(json::accept(vu.begin(), vu.end()) == expected_accept);
const std::vector<signed char> vs = bytes_as<signed char>(text);
CHECK(outcome_of(vs.begin(), vs.end()) == expected);
}
} // namespace
TEST_CASE("deserialization from iterator pairs of std::string and std::vector")
{
// these are read as the pointer range they are, also before C++20
for (const char* text :
{
"", " ", R"([1, 2.5, "a", true, null, {"k": ["v"]}])", "[1, 2", R"({"a" 1})", "\"\xC3\xA4\"", "\"\xC3\"", "[1]x", "1e400"
})
{
check_iterator_pairs(text);
}
check_iterator_pairs(std::string("[1]" "\0" "x", 5));
// an empty range is not dereferenced
std::string empty;
CHECK_FALSE(json::accept(empty.begin(), empty.end()));
json _;
CHECK_THROWS_AS(_ = json::parse(empty.begin(), empty.end()), json::parse_error&);
}
#endif