deploy: 4e294f4b18

api/basic_json/array_t.md

@@ -27,7 +27,7 @@ To store objects in C++, a type is defined by the template parameters explained
 
 ### Default type
 
-With the default values for `ArrayType` (`std::vector`) and `AllocatorType` (`std::allocator`), the default value for
+With the default values for `ArrayType` (`std::vector`) and `AllocatorType` (`std::allocator`), the default type for
 `array_t` is:
 
 ```cpp

api/basic_json/array_t/index.md

@@ -22,7 +22,7 @@ To store objects in C++, a type is defined by the template parameters explained
 
 ### Default type
 
-With the default values for `ArrayType` (`std::vector`) and `AllocatorType` (`std::allocator`), the default value for `array_t` is:
+With the default values for `ArrayType` (`std::vector`) and `AllocatorType` (`std::allocator`), the default type for `array_t` is:
 
 ```
 std::vector<

api/basic_json/boolean_t.md

@@ -23,7 +23,7 @@ To store boolean values in C++, a type is defined by the template parameter  `Bo
 
 ### Default type
 
-With the default values for `BooleanType` (`#!cpp bool`), the default value for `boolean_t` is `#!cpp bool`.
+With the default values for `BooleanType` (`#!cpp bool`), the default type for `boolean_t` is `#!cpp bool`.
 
 ### Storage
 

api/basic_json/boolean_t/index.md

@@ -18,7 +18,7 @@ To store boolean values in C++, a type is defined by the template parameter `Boo
 
 ### Default type
 
-With the default values for `BooleanType` (`bool`), the default value for `boolean_t` is `bool`.
+With the default values for `BooleanType` (`bool`), the default type for `boolean_t` is `bool`.
 
 ### Storage
 

api/basic_json/dump.md

@@ -62,6 +62,9 @@ Linear.
 
 ## Notes
 
+Floating-point numbers are written with the fewest digits that read back as the same value (for `#!cpp double`; see
+[number handling](../../features/types/number_handling.md#number-serialization)).
+
 Binary values are serialized as an object containing two keys:
 
 - "bytes": an array of bytes as integers
@@ -200,3 +203,5 @@ Binary values are serialized as an object containing two keys:
 - Error handlers added in version 3.4.0.
 - Serialization of binary values added in version 3.8.0.
 - Error handler `keep` added in version 3.13.0.
+- Doubles are written with the shortest digits (Żmij instead of Grisu2) since version 3.13.0; about 0.1% of doubles are
+  written differently, most of them with fewer digits.

api/basic_json/dump/index.md

@@ -43,6 +43,8 @@ Linear.
 
 ## Notes
 
+Floating-point numbers are written with the fewest digits that read back as the same value (for `double`; see [number handling](https://json.nlohmann.me/features/types/number_handling/#number-serialization)).
+
 Binary values are serialized as an object containing two keys:
 
 - "bytes": an array of bytes as integers
@@ -178,3 +180,4 @@ string with ignored invalid characters: "äü"
 - Error handlers added in version 3.4.0.
 - Serialization of binary values added in version 3.8.0.
 - Error handler `keep` added in version 3.13.0 unreleased.
+- Doubles are written with the shortest digits (Żmij instead of Grisu2) since version 3.13.0 unreleased; about 0.1% of doubles are written differently, most of them with fewer digits.

api/basic_json/index.md

@@ -68,7 +68,7 @@ The class satisfies the following concept requirements:
 ### Library-wide
 
 - [EqualityComparable](https://en.cppreference.com/w/cpp/named_req/EqualityComparable): JSON values can be compared with `==`, see [`operator==`](https://json.nlohmann.me/api/basic_json/operator_eq/index.md).
-- [LessThanComparable](https://en.cppreference.com/w/cpp/named_req/LessThanComparable): JSON values can be compared with `<`, see [`operator<`](https://json.nlohmann.me/api/basic_json/operator_le/index.md).
+- [LessThanComparable](https://en.cppreference.com/w/cpp/named_req/LessThanComparable): JSON values can be compared with `<`, see [`operator<`](https://json.nlohmann.me/api/basic_json/operator_lt/index.md).
 - [Swappable](https://en.cppreference.com/w/cpp/named_req/Swappable): Any JSON lvalue or rvalue of can be swapped with any lvalue or rvalue of other compatible types, using unqualified function `swap`.
 - [NullablePointer](https://en.cppreference.com/w/cpp/named_req/NullablePointer): JSON values can be compared against `std::nullptr_t` objects which are used to model the `null` value.
 

api/basic_json/merge_diff.md

@@ -11,7 +11,7 @@ added members with their new values, and removed members with the value `#!json
 member by member; any other value that differs, including an array, is replaced as a whole.
 
 For two JSON values `source` and `target`, where `target` contains no object member whose value is `#!json null`, the
-following code always yields `#!cpp true`:
+following code always yields `#!cpp true` (for [`ordered_json`](../ordered_json.md), see the notes below):
 ```cpp
 basic_json patched = source;
 patched.merge_patch(merge_diff(source, target));

api/basic_json/merge_diff/index.md

@@ -7,7 +7,7 @@ static basic_json merge_diff(const basic_json& source,
 
 Creates a [JSON Merge Patch](https://tools.ietf.org/html/rfc7396) so that value `source` can be changed into the value `target` by calling the [`merge_patch`](https://json.nlohmann.me/api/basic_json/merge_patch/index.md) function. The patch contains only what differs: changed and added members with their new values, and removed members with the value `null`. Nested objects are compared member by member; any other value that differs, including an array, is replaced as a whole.
 
-For two JSON values `source` and `target`, where `target` contains no object member whose value is `null`, the following code always yields `true`:
+For two JSON values `source` and `target`, where `target` contains no object member whose value is `null`, the following code always yields `true` (for [`ordered_json`](https://json.nlohmann.me/api/ordered_json/index.md), see the notes below):
 
 ```
 basic_json patched = source;

api/basic_json/number_float_t.md

@@ -23,9 +23,10 @@ type to use.
 ## Template parameters
 
 `NumberFloatType`
-:   the type to store floating-point numbers. Parsing and serialization are implemented in terms of
-    `#!cpp std::strtof`/`#!cpp std::strtod`/`#!cpp std::strtold` and `#!cpp std::snprintf`, so the type must be
-    `#!cpp float`, `#!cpp double`, or `#!cpp long double`. The
+:   the type to store floating-point numbers. The type must be `#!cpp float`, `#!cpp double`, or
+    `#!cpp long double`. The parser converts `#!cpp float`, `#!cpp double`, and a `#!cpp long double` that is IEEE 754
+    binary64 itself. It converts other `#!cpp long double` formats with `#!cpp std::from_chars` where available, or
+    with `#!cpp std::strtold` otherwise. Serialization falls back to `#!cpp std::snprintf`. The
     [binary formats](../../features/binary_formats/index.md) additionally require `#!cpp float` or `#!cpp double`,
     because they have no encoding for `#!cpp long double`. See
     [Template Parameter Requirements](../../features/types/template_parameters.md#numberfloattype).
@@ -34,7 +35,7 @@ type to use.
 
 ### Default type
 
-With the default values for `NumberFloatType` (`double`), the default value for `number_float_t` is `#!cpp double`.
+With the default values for `NumberFloatType` (`double`), the default type for `number_float_t` is `#!cpp double`.
 
 ### Default behavior
 
@@ -51,9 +52,11 @@ With the default values for `NumberFloatType` (`double`), the default value for
 > interoperability can be achieved by implementations that expect no more precision or range than these provide, in the
 > sense that implementations will approximate JSON numbers within the expected precision.
 
-This implementation does exactly follow this approach, as it uses double precision floating-point numbers. Note values
-smaller than `-1.79769313486232e+308` and values greater than `1.79769313486232e+308` will be stored as NaN internally
-and be serialized to `null`.
+This implementation does exactly follow this approach, as it uses double precision floating-point numbers by default.
+Note that with the default `double`, numbers smaller than `-1.79769313486232e+308` or greater than
+`1.79769313486232e+308` are rejected during parsing with
+[`out_of_range.406`](../../home/exceptions.md#jsonexceptionout_of_range406). Non-finite values (NaN and infinity) can
+only be stored by assigning them directly and are serialized to `null`.
 
 During deserialization (from JSON text or any of the binary formats), a finite number that does not fit into
 `number_float_t` is rejected with [`out_of_range.406`](../../home/exceptions.md#jsonexceptionout_of_range406), for

api/basic_json/number_float_t/index.md

@@ -16,13 +16,13 @@ To store floating-point numbers in C++, a type is defined by the template parame
 
 ## Template parameters
 
-`NumberFloatType` : the type to store floating-point numbers. Parsing and serialization are implemented in terms of `std::strtof`/`std::strtod`/`std::strtold` and `std::snprintf`, so the type must be `float`, `double`, or `long double`. The [binary formats](https://json.nlohmann.me/features/binary_formats/index.md) additionally require `float` or `double`, because they have no encoding for `long double`. See [Template Parameter Requirements](https://json.nlohmann.me/features/types/template_parameters/#numberfloattype).
+`NumberFloatType` : the type to store floating-point numbers. The type must be `float`, `double`, or `long double`. The parser converts `float`, `double`, and a `long double` that is IEEE 754 binary64 itself. It converts other `long double` formats with `std::from_chars` where available, or with `std::strtold` otherwise. Serialization falls back to `std::snprintf`. The [binary formats](https://json.nlohmann.me/features/binary_formats/index.md) additionally require `float` or `double`, because they have no encoding for `long double`. See [Template Parameter Requirements](https://json.nlohmann.me/features/types/template_parameters/#numberfloattype).
 
 ## Notes
 
 ### Default type
 
-With the default values for `NumberFloatType` (`double`), the default value for `number_float_t` is `double`.
+With the default values for `NumberFloatType` (`double`), the default type for `number_float_t` is `double`.
 
 ### Default behavior
 
@@ -35,7 +35,7 @@ With the default values for `NumberFloatType` (`double`), the default value for
 
 > This specification allows implementations to set limits on the range and precision of numbers accepted. Since software that implements IEEE 754-2008 binary64 (double precision) numbers is generally available and widely used, good interoperability can be achieved by implementations that expect no more precision or range than these provide, in the sense that implementations will approximate JSON numbers within the expected precision.
 
-This implementation does exactly follow this approach, as it uses double precision floating-point numbers. Note values smaller than `-1.79769313486232e+308` and values greater than `1.79769313486232e+308` will be stored as NaN internally and be serialized to `null`.
+This implementation does exactly follow this approach, as it uses double precision floating-point numbers by default. Note that with the default `double`, numbers smaller than `-1.79769313486232e+308` or greater than `1.79769313486232e+308` are rejected during parsing with [`out_of_range.406`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range406). Non-finite values (NaN and infinity) can only be stored by assigning them directly and are serialized to `null`.
 
 During deserialization (from JSON text or any of the binary formats), a finite number that does not fit into `number_float_t` is rejected with [`out_of_range.406`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range406), for example a double-precision number in a binary format when `number_float_t` is `float`.
 

api/basic_json/number_integer_t.md

@@ -31,7 +31,7 @@ to use.
 
 ### Default type
 
-With the default values for `NumberIntegerType` (`std::int64_t`), the default value for `number_integer_t` is
+With the default values for `NumberIntegerType` (`std::int64_t`), the default type for `number_integer_t` is
 `#!cpp std::int64_t`.
 
 ### Default behavior

api/basic_json/number_integer_t/index.md

@@ -22,7 +22,7 @@ To store integer numbers in C++, a type is defined by the template parameter `Nu
 
 ### Default type
 
-With the default values for `NumberIntegerType` (`std::int64_t`), the default value for `number_integer_t` is `std::int64_t`.
+With the default values for `NumberIntegerType` (`std::int64_t`), the default type for `number_integer_t` is `std::int64_t`.
 
 ### Default behavior
 

api/basic_json/number_unsigned_t.md

@@ -32,7 +32,7 @@ the type to use.
 
 ### Default type
 
-With the default values for `NumberUnsignedType` (`std::uint64_t`), the default value for `number_unsigned_t` is
+With the default values for `NumberUnsignedType` (`std::uint64_t`), the default type for `number_unsigned_t` is
 `#!cpp std::uint64_t`.
 
 ### Default behavior

api/basic_json/number_unsigned_t/index.md

@@ -22,7 +22,7 @@ To store unsigned integer numbers in C++, a type is defined by the template para
 
 ### Default type
 
-With the default values for `NumberUnsignedType` (`std::uint64_t`), the default value for `number_unsigned_t` is `std::uint64_t`.
+With the default values for `NumberUnsignedType` (`std::uint64_t`), the default type for `number_unsigned_t` is `std::uint64_t`.
 
 ### Default behavior
 

api/basic_json/object_t.md

@@ -36,7 +36,7 @@ To store objects in C++, a type is defined by the template parameters described
 ### Default type
 
 With the default values for `ObjectType` (`std::map`), `StringType` (`std::string`), and `AllocatorType`
-(`std::allocator`), the default value for `object_t` is:
+(`std::allocator`), the default type for `object_t` is:
 
 ```cpp
 // until C++14

api/basic_json/object_t/index.md

@@ -27,7 +27,7 @@ To store objects in C++, a type is defined by the template parameters described
 
 ### Default type
 
-With the default values for `ObjectType` (`std::map`), `StringType` (`std::string`), and `AllocatorType` (`std::allocator`), the default value for `object_t` is:
+With the default values for `ObjectType` (`std::map`), `StringType` (`std::string`), and `AllocatorType` (`std::allocator`), the default type for `object_t` is:
 
 ```
 // until C++14

api/basic_json/operator_eq.md

@@ -20,7 +20,8 @@ bool operator==(ScalarType rhs) const noexcept(/* see below */); // (2)
 1. Compares two JSON values for equality according to the following rules:
     - Two JSON values are equal if (1) neither value is discarded, and (2) they are of the same type and their stored
       values are the same according to their respective `operator==`.
-    - Integer and floating-point numbers are automatically converted before comparison.
+    - Integer and floating-point numbers are compared by their exact values, without converting the integer to
+      floating-point. For instance, `9007199254740993` and `9007199254740992.0` are not equal.
 
 2. Compares a JSON value and a scalar or a scalar and a JSON value for equality by converting the
    scalar to a JSON value and comparing both JSON values according to 1.

api/basic_json/operator_eq/index.md

@@ -20,7 +20,7 @@ bool operator==(ScalarType rhs) const noexcept(/* see below */); // (2)
 1. Compares two JSON values for equality according to the following rules:
 
    - Two JSON values are equal if (1) neither value is discarded, and (2) they are of the same type and their stored values are the same according to their respective `operator==`.
-   - Integer and floating-point numbers are automatically converted before comparison.
+   - Integer and floating-point numbers are compared by their exact values, without converting the integer to floating-point. For instance, `9007199254740993` and `9007199254740992.0` are not equal.
 
 1. Compares a JSON value and a scalar or a scalar and a JSON value for equality by converting the scalar to a JSON value and comparing both JSON values according to 1.
 

api/basic_json/operator_lt.md

@@ -15,7 +15,8 @@ bool operator<(ScalarType lhs, const const_reference rhs) noexcept(/* see below
   following rules:
     - If either operand is discarded, the comparison yields `#!cpp false`.
     - If both operands have the same type, the values are compared using their respective `operator<`.
-    - Integer and floating-point numbers are automatically converted before comparison.
+    - Integer and floating-point numbers are compared by their exact values, without converting the integer to
+      floating-point. For instance, `9007199254740992.0` is less than `9007199254740993`.
     - In case `lhs` and `rhs` have different types, the values are ignored and the order of the types
       is considered, which is:
         1. null

api/basic_json/operator_lt/index.md

@@ -15,7 +15,7 @@ bool operator<(ScalarType lhs, const const_reference rhs) noexcept(/* see below
 
    - If either operand is discarded, the comparison yields `false`.
    - If both operands have the same type, the values are compared using their respective `operator<`.
-   - Integer and floating-point numbers are automatically converted before comparison.
+   - Integer and floating-point numbers are compared by their exact values, without converting the integer to floating-point. For instance, `9007199254740992.0` is less than `9007199254740993`.
    - In case `lhs` and `rhs` have different types, the values are ignored and the order of the types is considered, which is:
      1. null
      1. boolean

api/basic_json/operator_spaceship.md

@@ -12,10 +12,8 @@ std::partial_ordering operator<=>(const ScalarType rhs) const noexcept(/* see be
     - Two JSON values compare with a result of `std::partial_ordering::unordered` if either value is discarded.
     - If both JSON values are of the same type, the result is produced by 3-way comparing their stored values using
       their respective `operator<=>`.
-    - Integer and floating-point numbers are converted to their common type and then 3-way compared using their
-      respective `operator<=>`.
-      For instance, comparing an integer and a floating-point value will 3-way compare the first value converted to
-      floating-point with the second value.
+    - Integer and floating-point numbers are 3-way compared by their exact values, without converting the integer to
+      floating-point. For instance, `9007199254740993` compares greater than `9007199254740992.0`.
     - Otherwise, yields a result by comparing the type (see [`value_t`](value_t.md)).
   
 2. 3-way compares a JSON value and a scalar or a scalar and a JSON value by converting the scalar to a JSON value and

api/basic_json/operator_spaceship/index.md

@@ -12,7 +12,7 @@ std::partial_ordering operator<=>(const ScalarType rhs) const noexcept(/* see be
 
    - Two JSON values compare with a result of `std::partial_ordering::unordered` if either value is discarded.
    - If both JSON values are of the same type, the result is produced by 3-way comparing their stored values using their respective `operator<=>`.
-   - Integer and floating-point numbers are converted to their common type and then 3-way compared using their respective `operator<=>`. For instance, comparing an integer and a floating-point value will 3-way compare the first value converted to floating-point with the second value.
+   - Integer and floating-point numbers are 3-way compared by their exact values, without converting the integer to floating-point. For instance, `9007199254740993` compares greater than `9007199254740992.0`.
    - Otherwise, yields a result by comparing the type (see [`value_t`](https://json.nlohmann.me/api/basic_json/value_t/index.md)).
 
 1. 3-way compares a JSON value and a scalar or a scalar and a JSON value by converting the scalar to a JSON value and 3-way comparing both JSON values (see 1).

api/basic_json/patch.md

@@ -45,7 +45,7 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
   pointer inside the patch cannot be resolved, e.g., `-` in a "remove" operation or `1a` for an array; example:
   `"unresolved reference token '-'"`.
 - Throws [`out_of_range.405`](../../home/exceptions.md#jsonexceptionout_of_range405) if JSON pointer has no parent
-  ("add", "remove", "move")
+  ("remove", "move")
 - Throws [`out_of_range.411`](../../home/exceptions.md#jsonexceptionout_of_range411) if an "add" operation's target
   location has a parent that is neither an object nor an array.
 - Throws [`out_of_range.413`](../../home/exceptions.md#jsonexceptionout_of_range413) if a "remove" operation's target

api/basic_json/patch/index.md

@@ -30,7 +30,7 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
 - Throws [`out_of_range.402`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range402) if the array index `-` is used where an existing element is required (the "path" of "replace", the "from" of "move" and "copy"); example: `"array index '-' (3) is out of range"`.
 - Throws [`out_of_range.403`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range403) if a JSON pointer inside the patch could not be resolved successfully in the current JSON value; example: `"key baz not found"`.
 - Throws [`out_of_range.404`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range404) if a reference token of a JSON pointer inside the patch cannot be resolved, e.g., `-` in a "remove" operation or `1a` for an array; example: `"unresolved reference token '-'"`.
-- Throws [`out_of_range.405`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range405) if JSON pointer has no parent ("add", "remove", "move")
+- Throws [`out_of_range.405`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range405) if JSON pointer has no parent ("remove", "move")
 - Throws [`out_of_range.411`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range411) if an "add" operation's target location has a parent that is neither an object nor an array.
 - Throws [`out_of_range.413`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range413) if a "remove" operation's target location has a parent that is neither an object nor an array.
 - Throws [`out_of_range.414`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range414) if a "move" operation's "from" location is a proper prefix of its "path" location.

api/basic_json/patch_inplace.md

@@ -41,7 +41,7 @@ No guarantees, value may be corrupted by an unsuccessful patch operation.
   pointer inside the patch cannot be resolved, e.g., `-` in a "remove" operation or `1a` for an array; example:
   `"unresolved reference token '-'"`.
 - Throws [`out_of_range.405`](../../home/exceptions.md#jsonexceptionout_of_range405) if JSON pointer has no parent
-  ("add", "remove", "move")
+  ("remove", "move")
 - Throws [`out_of_range.411`](../../home/exceptions.md#jsonexceptionout_of_range411) if an "add" operation's target
   location has a parent that is neither an object nor an array.
 - Throws [`out_of_range.413`](../../home/exceptions.md#jsonexceptionout_of_range413) if a "remove" operation's target

api/basic_json/patch_inplace/index.md

@@ -26,7 +26,7 @@ No guarantees, value may be corrupted by an unsuccessful patch operation.
 - Throws [`out_of_range.402`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range402) if the array index `-` is used where an existing element is required (the "path" of "replace", the "from" of "move" and "copy"); example: `"array index '-' (3) is out of range"`.
 - Throws [`out_of_range.403`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range403) if a JSON pointer inside the patch could not be resolved successfully in the current JSON value; example: `"key baz not found"`.
 - Throws [`out_of_range.404`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range404) if a reference token of a JSON pointer inside the patch cannot be resolved, e.g., `-` in a "remove" operation or `1a` for an array; example: `"unresolved reference token '-'"`.
-- Throws [`out_of_range.405`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range405) if JSON pointer has no parent ("add", "remove", "move")
+- Throws [`out_of_range.405`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range405) if JSON pointer has no parent ("remove", "move")
 - Throws [`out_of_range.411`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range411) if an "add" operation's target location has a parent that is neither an object nor an array.
 - Throws [`out_of_range.413`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range413) if a "remove" operation's target location has a parent that is neither an object nor an array.
 - Throws [`out_of_range.414`](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range414) if a "move" operation's "from" location is a proper prefix of its "path" location.

api/basic_json/string_t.md

@@ -32,7 +32,7 @@ JSON class into byte-sized characters during deserialization.
 
 ### Default type
 
-With the default values for `StringType` (`std::string`), the default value for `string_t` is `#!cpp std::string`.
+With the default values for `StringType` (`std::string`), the default type for `string_t` is `#!cpp std::string`.
 
 ### Encoding
 

api/basic_json/string_t/index.md

@@ -32,7 +32,7 @@ for the string types that are known to work.
 
 ### Default type
 
-With the default values for `StringType` (`std::string`), the default value for `string_t` is `std::string`.
+With the default values for `StringType` (`std::string`), the default type for `string_t` is `std::string`.
 
 ### Encoding