🔥 consolidate documentation

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Niels Lohmann 2021-10-16 14:10:09 +02:00
parent 17a31bf503
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4 changed files with 72 additions and 820 deletions

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@ -14,8 +14,8 @@ reference at(const json_pointer& ptr);
const_reference at(const json_pointer& ptr) const;
```
1. Returns a reference to the element at specified location `idx`, with bounds checking.
2. Returns a reference to the element at with specified key `key`, with bounds checking.
1. Returns a reference to the array element at specified location `idx`, with bounds checking.
2. Returns a reference to the object element at with specified key `key`, with bounds checking.
3. Returns a reference to the element at with specified JSON pointer `ptr`, with bounds checking.
## Parameters
@ -74,7 +74,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
## Example
??? example
??? example "Example: (1) access specified array element with bounds checking"
The example below shows how array elements can be read and written using `at()`. It also demonstrates the different
exceptions that can be thrown.
@ -89,7 +89,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
--8<-- "examples/at__size_type.output"
```
??? example
??? example "Example: (1) access specified array element with bounds checking"
The example below shows how array elements can be read using `at()`. It also demonstrates the different exceptions
that can be thrown.
@ -104,7 +104,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
--8<-- "examples/at__size_type_const.output"
```
??? example
??? example "Example: (2) access specified object element with bounds checking"
The example below shows how object elements can be read and written using `at()`. It also demonstrates the different
exceptions that can be thrown.
@ -119,7 +119,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
--8<-- "examples/at__object_t_key_type.output"
```
??? example
??? example "Example (2) access specified object element with bounds checking"
The example below shows how object elements can be read using `at()`. It also demonstrates the different exceptions
that can be thrown.
@ -134,7 +134,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
--8<-- "examples/at__object_t_key_type_const.output"
```
??? example
??? example "Example (3) access specified element via JSON Pointer"
The example below shows how object elements can be read and written using `at()`. It also demonstrates the different
exceptions that can be thrown.
@ -149,7 +149,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
--8<-- "examples/at_json_pointer.output"
```
??? example
??? example "Example (3) access specified element via JSON Pointer"
The example below shows how object elements can be read using `at()`. It also demonstrates the different exceptions
that can be thrown.

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@ -18,8 +18,8 @@ reference operator[](const json_pointer& ptr);
const_reference operator[](const json_pointer& ptr) const;
```
1. Returns a reference to the element at specified location `idx`.
2. Returns a reference to the element at with specified key `key`.
1. Returns a reference to the array element at specified location `idx`.
2. Returns a reference to the object element at with specified key `key`.
3. Returns a reference to the element at with specified JSON pointer `ptr`.
## Template parameters
@ -99,7 +99,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
## Example
??? example
??? example "Example (1): access specified array element"
The example below shows how array elements can be read and written using `[]` operator. Note the addition of
`#!json null` values.
@ -114,7 +114,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
--8<-- "examples/operatorarray__size_type.output"
```
??? example
??? example "Example (1): access specified array element"
The example below shows how array elements can be read using the `[]` operator.
@ -128,7 +128,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
--8<-- "examples/operatorarray__size_type_const.output"
```
??? example
??? example "Example (2): access specified object element"
The example below shows how object elements can be read and written using the `[]` operator.
@ -142,7 +142,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
--8<-- "examples/operatorarray__key_type.output"
```
??? example
??? example "Example (2): access specified object element"
The example below shows how object elements can be read using the `[]` operator.
@ -156,7 +156,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
--8<-- "examples/operatorarray__key_type_const.output"
```
??? example
??? example "Example (3): access specified element via JSON Pointer"
The example below shows how values can be read and written using JSON Pointers.
@ -170,7 +170,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
--8<-- "examples/operatorjson_pointer.output"
```
??? example
??? example "Example (3): access specified element via JSON Pointer"
The example below shows how values can be read using JSON Pointers.

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@ -2067,32 +2067,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
/// Access to the JSON value.
/// @{
/*!
@brief access specified array element with bounds checking
Returns a reference to the element at specified location @a idx, with
bounds checking.
@param[in] idx index of the element to access
@return reference to the element at index @a idx
@throw type_error.304 if the JSON value is not an array; in this case,
calling `at` with an index makes no sense. See example below.
@throw out_of_range.401 if the index @a idx is out of range of the array;
that is, `idx >= size()`. See example below.
@exceptionsafety Strong guarantee: if an exception is thrown, there are no
changes in the JSON value.
@complexity Constant.
@since version 1.0.0
@liveexample{The example below shows how array elements can be read and
written using `at()`. It also demonstrates the different exceptions that
can be thrown.,at__size_type}
*/
/// @brief access specified array element with bounds checking
/// @sa https://json.nlohmann.me/api/basic_json/at/
reference at(size_type idx)
{
// at only works for arrays
@ -2114,32 +2090,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
}
}
/*!
@brief access specified array element with bounds checking
Returns a const reference to the element at specified location @a idx,
with bounds checking.
@param[in] idx index of the element to access
@return const reference to the element at index @a idx
@throw type_error.304 if the JSON value is not an array; in this case,
calling `at` with an index makes no sense. See example below.
@throw out_of_range.401 if the index @a idx is out of range of the array;
that is, `idx >= size()`. See example below.
@exceptionsafety Strong guarantee: if an exception is thrown, there are no
changes in the JSON value.
@complexity Constant.
@since version 1.0.0
@liveexample{The example below shows how array elements can be read using
`at()`. It also demonstrates the different exceptions that can be thrown.,
at__size_type_const}
*/
/// @brief access specified array element with bounds checking
/// @sa https://json.nlohmann.me/api/basic_json/at/
const_reference at(size_type idx) const
{
// at only works for arrays
@ -2161,36 +2113,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
}
}
/*!
@brief access specified object element with bounds checking
Returns a reference to the element at with specified key @a key, with
bounds checking.
@param[in] key key of the element to access
@return reference to the element at key @a key
@throw type_error.304 if the JSON value is not an object; in this case,
calling `at` with a key makes no sense. See example below.
@throw out_of_range.403 if the key @a key is is not stored in the object;
that is, `find(key) == end()`. See example below.
@exceptionsafety Strong guarantee: if an exception is thrown, there are no
changes in the JSON value.
@complexity Logarithmic in the size of the container.
@sa see @ref operator[](const typename object_t::key_type&) for unchecked
access by reference
@sa see @ref value() for access by value with a default value
@since version 1.0.0
@liveexample{The example below shows how object elements can be read and
written using `at()`. It also demonstrates the different exceptions that
can be thrown.,at__object_t_key_type}
*/
/// @brief access specified object element with bounds checking
/// @sa https://json.nlohmann.me/api/basic_json/at/
reference at(const typename object_t::key_type& key)
{
// at only works for objects
@ -2212,36 +2136,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
}
}
/*!
@brief access specified object element with bounds checking
Returns a const reference to the element at with specified key @a key,
with bounds checking.
@param[in] key key of the element to access
@return const reference to the element at key @a key
@throw type_error.304 if the JSON value is not an object; in this case,
calling `at` with a key makes no sense. See example below.
@throw out_of_range.403 if the key @a key is is not stored in the object;
that is, `find(key) == end()`. See example below.
@exceptionsafety Strong guarantee: if an exception is thrown, there are no
changes in the JSON value.
@complexity Logarithmic in the size of the container.
@sa see @ref operator[](const typename object_t::key_type&) for unchecked
access by reference
@sa see @ref value() for access by value with a default value
@since version 1.0.0
@liveexample{The example below shows how object elements can be read using
`at()`. It also demonstrates the different exceptions that can be thrown.,
at__object_t_key_type_const}
*/
/// @brief access specified object element with bounds checking
/// @sa https://json.nlohmann.me/api/basic_json/at/
const_reference at(const typename object_t::key_type& key) const
{
// at only works for objects
@ -2263,31 +2159,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
}
}
/*!
@brief access specified array element
Returns a reference to the element at specified location @a idx.
@note If @a idx is beyond the range of the array (i.e., `idx >= size()`),
then the array is silently filled up with `null` values to make `idx` a
valid reference to the last stored element.
@param[in] idx index of the element to access
@return reference to the element at index @a idx
@throw type_error.305 if the JSON value is not an array or null; in that
cases, using the [] operator with an index makes no sense.
@complexity Constant if @a idx is in the range of the array. Otherwise
linear in `idx - size()`.
@liveexample{The example below shows how array elements can be read and
written using `[]` operator. Note the addition of `null`
values.,operatorarray__size_type}
@since version 1.0.0
*/
/// @brief access specified array element
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
reference operator[](size_type idx)
{
// implicitly convert null value to an empty array
@ -2332,25 +2205,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
JSON_THROW(type_error::create(305, "cannot use operator[] with a numeric argument with " + std::string(type_name()), *this));
}
/*!
@brief access specified array element
Returns a const reference to the element at specified location @a idx.
@param[in] idx index of the element to access
@return const reference to the element at index @a idx
@throw type_error.305 if the JSON value is not an array; in that case,
using the [] operator with an index makes no sense.
@complexity Constant.
@liveexample{The example below shows how array elements can be read using
the `[]` operator.,operatorarray__size_type_const}
@since version 1.0.0
*/
/// @brief access specified array element
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
const_reference operator[](size_type idx) const
{
// const operator[] only works for arrays
@ -2362,33 +2218,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
JSON_THROW(type_error::create(305, "cannot use operator[] with a numeric argument with " + std::string(type_name()), *this));
}
/*!
@brief access specified object element
Returns a reference to the element at with specified key @a key.
@note If @a key is not found in the object, then it is silently added to
the object and filled with a `null` value to make `key` a valid reference.
In case the value was `null` before, it is converted to an object.
@param[in] key key of the element to access
@return reference to the element at key @a key
@throw type_error.305 if the JSON value is not an object or null; in that
cases, using the [] operator with a key makes no sense.
@complexity Logarithmic in the size of the container.
@liveexample{The example below shows how object elements can be read and
written using the `[]` operator.,operatorarray__key_type}
@sa see @ref at(const typename object_t::key_type&) for access by reference
with range checking
@sa see @ref value() for access by value with a default value
@since version 1.0.0
*/
/// @brief access specified object element
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
reference operator[](const typename object_t::key_type& key)
{
// implicitly convert null value to an empty object
@ -2408,36 +2239,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
JSON_THROW(type_error::create(305, "cannot use operator[] with a string argument with " + std::string(type_name()), *this));
}
/*!
@brief read-only access specified object element
Returns a const reference to the element at with specified key @a key. No
bounds checking is performed.
@warning If the element with key @a key does not exist, the behavior is
undefined.
@param[in] key key of the element to access
@return const reference to the element at key @a key
@pre The element with key @a key must exist. **This precondition is
enforced with an assertion.**
@throw type_error.305 if the JSON value is not an object; in that case,
using the [] operator with a key makes no sense.
@complexity Logarithmic in the size of the container.
@liveexample{The example below shows how object elements can be read using
the `[]` operator.,operatorarray__key_type_const}
@sa see @ref at(const typename object_t::key_type&) for access by reference
with range checking
@sa see @ref value() for access by value with a default value
@since version 1.0.0
*/
/// @brief access specified object element
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
const_reference operator[](const typename object_t::key_type& key) const
{
// const operator[] only works for objects
@ -2450,33 +2253,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
JSON_THROW(type_error::create(305, "cannot use operator[] with a string argument with " + std::string(type_name()), *this));
}
/*!
@brief access specified object element
Returns a reference to the element at with specified key @a key.
@note If @a key is not found in the object, then it is silently added to
the object and filled with a `null` value to make `key` a valid reference.
In case the value was `null` before, it is converted to an object.
@param[in] key key of the element to access
@return reference to the element at key @a key
@throw type_error.305 if the JSON value is not an object or null; in that
cases, using the [] operator with a key makes no sense.
@complexity Logarithmic in the size of the container.
@liveexample{The example below shows how object elements can be read and
written using the `[]` operator.,operatorarray__key_type}
@sa see @ref at(const typename object_t::key_type&) for access by reference
with range checking
@sa see @ref value() for access by value with a default value
@since version 1.1.0
*/
/// @brief access specified object element
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
template<typename T>
JSON_HEDLEY_NON_NULL(2)
reference operator[](T* key)
@ -2498,36 +2276,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
JSON_THROW(type_error::create(305, "cannot use operator[] with a string argument with " + std::string(type_name()), *this));
}
/*!
@brief read-only access specified object element
Returns a const reference to the element at with specified key @a key. No
bounds checking is performed.
@warning If the element with key @a key does not exist, the behavior is
undefined.
@param[in] key key of the element to access
@return const reference to the element at key @a key
@pre The element with key @a key must exist. **This precondition is
enforced with an assertion.**
@throw type_error.305 if the JSON value is not an object; in that case,
using the [] operator with a key makes no sense.
@complexity Logarithmic in the size of the container.
@liveexample{The example below shows how object elements can be read using
the `[]` operator.,operatorarray__key_type_const}
@sa see @ref at(const typename object_t::key_type&) for access by reference
with range checking
@sa see @ref value() for access by value with a default value
@since version 1.1.0
*/
/// @brief access specified object element
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
template<typename T>
JSON_HEDLEY_NON_NULL(2)
const_reference operator[](T* key) const
@ -5382,153 +5132,29 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
/// @name JSON Pointer functions
/// @{
/*!
@brief access specified element via JSON Pointer
Uses a JSON pointer to retrieve a reference to the respective JSON value.
No bound checking is performed. Similar to @ref operator[](const typename
object_t::key_type&), `null` values are created in arrays and objects if
necessary.
In particular:
- If the JSON pointer points to an object key that does not exist, it
is created an filled with a `null` value before a reference to it
is returned.
- If the JSON pointer points to an array index that does not exist, it
is created an filled with a `null` value before a reference to it
is returned. All indices between the current maximum and the given
index are also filled with `null`.
- The special value `-` is treated as a synonym for the index past the
end.
@param[in] ptr a JSON pointer
@return reference to the element pointed to by @a ptr
@complexity Constant.
@throw parse_error.106 if an array index begins with '0'
@throw parse_error.109 if an array index was not a number
@throw out_of_range.404 if the JSON pointer can not be resolved
@liveexample{The behavior is shown in the example.,operatorjson_pointer}
@since version 2.0.0
*/
/// @brief access specified element via JSON Pointer
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
reference operator[](const json_pointer& ptr)
{
return ptr.get_unchecked(this);
}
/*!
@brief access specified element via JSON Pointer
Uses a JSON pointer to retrieve a reference to the respective JSON value.
No bound checking is performed. The function does not change the JSON
value; no `null` values are created. In particular, the special value
`-` yields an exception.
@param[in] ptr JSON pointer to the desired element
@return const reference to the element pointed to by @a ptr
@complexity Constant.
@throw parse_error.106 if an array index begins with '0'
@throw parse_error.109 if an array index was not a number
@throw out_of_range.402 if the array index '-' is used
@throw out_of_range.404 if the JSON pointer can not be resolved
@liveexample{The behavior is shown in the example.,operatorjson_pointer_const}
@since version 2.0.0
*/
/// @brief access specified element via JSON Pointer
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
const_reference operator[](const json_pointer& ptr) const
{
return ptr.get_unchecked(this);
}
/*!
@brief access specified element via JSON Pointer
Returns a reference to the element at with specified JSON pointer @a ptr,
with bounds checking.
@param[in] ptr JSON pointer to the desired element
@return reference to the element pointed to by @a ptr
@throw parse_error.106 if an array index in the passed JSON pointer @a ptr
begins with '0'. See example below.
@throw parse_error.109 if an array index in the passed JSON pointer @a ptr
is not a number. See example below.
@throw out_of_range.401 if an array index in the passed JSON pointer @a ptr
is out of range. See example below.
@throw out_of_range.402 if the array index '-' is used in the passed JSON
pointer @a ptr. As `at` provides checked access (and no elements are
implicitly inserted), the index '-' is always invalid. See example below.
@throw out_of_range.403 if the JSON pointer describes a key of an object
which cannot be found. See example below.
@throw out_of_range.404 if the JSON pointer @a ptr can not be resolved.
See example below.
@exceptionsafety Strong guarantee: if an exception is thrown, there are no
changes in the JSON value.
@complexity Constant.
@since version 2.0.0
@liveexample{The behavior is shown in the example.,at_json_pointer}
*/
/// @brief access specified element via JSON Pointer
/// @sa https://json.nlohmann.me/api/basic_json/at/
reference at(const json_pointer& ptr)
{
return ptr.get_checked(this);
}
/*!
@brief access specified element via JSON Pointer
Returns a const reference to the element at with specified JSON pointer @a
ptr, with bounds checking.
@param[in] ptr JSON pointer to the desired element
@return reference to the element pointed to by @a ptr
@throw parse_error.106 if an array index in the passed JSON pointer @a ptr
begins with '0'. See example below.
@throw parse_error.109 if an array index in the passed JSON pointer @a ptr
is not a number. See example below.
@throw out_of_range.401 if an array index in the passed JSON pointer @a ptr
is out of range. See example below.
@throw out_of_range.402 if the array index '-' is used in the passed JSON
pointer @a ptr. As `at` provides checked access (and no elements are
implicitly inserted), the index '-' is always invalid. See example below.
@throw out_of_range.403 if the JSON pointer describes a key of an object
which cannot be found. See example below.
@throw out_of_range.404 if the JSON pointer @a ptr can not be resolved.
See example below.
@exceptionsafety Strong guarantee: if an exception is thrown, there are no
changes in the JSON value.
@complexity Constant.
@since version 2.0.0
@liveexample{The behavior is shown in the example.,at_json_pointer_const}
*/
/// @brief access specified element via JSON Pointer
/// @sa https://json.nlohmann.me/api/basic_json/at/
const_reference at(const json_pointer& ptr) const
{
return ptr.get_checked(this);

View File

@ -19568,32 +19568,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
/// Access to the JSON value.
/// @{
/*!
@brief access specified array element with bounds checking
Returns a reference to the element at specified location @a idx, with
bounds checking.
@param[in] idx index of the element to access
@return reference to the element at index @a idx
@throw type_error.304 if the JSON value is not an array; in this case,
calling `at` with an index makes no sense. See example below.
@throw out_of_range.401 if the index @a idx is out of range of the array;
that is, `idx >= size()`. See example below.
@exceptionsafety Strong guarantee: if an exception is thrown, there are no
changes in the JSON value.
@complexity Constant.
@since version 1.0.0
@liveexample{The example below shows how array elements can be read and
written using `at()`. It also demonstrates the different exceptions that
can be thrown.,at__size_type}
*/
/// @brief access specified array element with bounds checking
/// @sa https://json.nlohmann.me/api/basic_json/at/
reference at(size_type idx)
{
// at only works for arrays
@ -19615,32 +19591,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
}
}
/*!
@brief access specified array element with bounds checking
Returns a const reference to the element at specified location @a idx,
with bounds checking.
@param[in] idx index of the element to access
@return const reference to the element at index @a idx
@throw type_error.304 if the JSON value is not an array; in this case,
calling `at` with an index makes no sense. See example below.
@throw out_of_range.401 if the index @a idx is out of range of the array;
that is, `idx >= size()`. See example below.
@exceptionsafety Strong guarantee: if an exception is thrown, there are no
changes in the JSON value.
@complexity Constant.
@since version 1.0.0
@liveexample{The example below shows how array elements can be read using
`at()`. It also demonstrates the different exceptions that can be thrown.,
at__size_type_const}
*/
/// @brief access specified array element with bounds checking
/// @sa https://json.nlohmann.me/api/basic_json/at/
const_reference at(size_type idx) const
{
// at only works for arrays
@ -19662,36 +19614,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
}
}
/*!
@brief access specified object element with bounds checking
Returns a reference to the element at with specified key @a key, with
bounds checking.
@param[in] key key of the element to access
@return reference to the element at key @a key
@throw type_error.304 if the JSON value is not an object; in this case,
calling `at` with a key makes no sense. See example below.
@throw out_of_range.403 if the key @a key is is not stored in the object;
that is, `find(key) == end()`. See example below.
@exceptionsafety Strong guarantee: if an exception is thrown, there are no
changes in the JSON value.
@complexity Logarithmic in the size of the container.
@sa see @ref operator[](const typename object_t::key_type&) for unchecked
access by reference
@sa see @ref value() for access by value with a default value
@since version 1.0.0
@liveexample{The example below shows how object elements can be read and
written using `at()`. It also demonstrates the different exceptions that
can be thrown.,at__object_t_key_type}
*/
/// @brief access specified object element with bounds checking
/// @sa https://json.nlohmann.me/api/basic_json/at/
reference at(const typename object_t::key_type& key)
{
// at only works for objects
@ -19713,36 +19637,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
}
}
/*!
@brief access specified object element with bounds checking
Returns a const reference to the element at with specified key @a key,
with bounds checking.
@param[in] key key of the element to access
@return const reference to the element at key @a key
@throw type_error.304 if the JSON value is not an object; in this case,
calling `at` with a key makes no sense. See example below.
@throw out_of_range.403 if the key @a key is is not stored in the object;
that is, `find(key) == end()`. See example below.
@exceptionsafety Strong guarantee: if an exception is thrown, there are no
changes in the JSON value.
@complexity Logarithmic in the size of the container.
@sa see @ref operator[](const typename object_t::key_type&) for unchecked
access by reference
@sa see @ref value() for access by value with a default value
@since version 1.0.0
@liveexample{The example below shows how object elements can be read using
`at()`. It also demonstrates the different exceptions that can be thrown.,
at__object_t_key_type_const}
*/
/// @brief access specified object element with bounds checking
/// @sa https://json.nlohmann.me/api/basic_json/at/
const_reference at(const typename object_t::key_type& key) const
{
// at only works for objects
@ -19764,31 +19660,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
}
}
/*!
@brief access specified array element
Returns a reference to the element at specified location @a idx.
@note If @a idx is beyond the range of the array (i.e., `idx >= size()`),
then the array is silently filled up with `null` values to make `idx` a
valid reference to the last stored element.
@param[in] idx index of the element to access
@return reference to the element at index @a idx
@throw type_error.305 if the JSON value is not an array or null; in that
cases, using the [] operator with an index makes no sense.
@complexity Constant if @a idx is in the range of the array. Otherwise
linear in `idx - size()`.
@liveexample{The example below shows how array elements can be read and
written using `[]` operator. Note the addition of `null`
values.,operatorarray__size_type}
@since version 1.0.0
*/
/// @brief access specified array element
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
reference operator[](size_type idx)
{
// implicitly convert null value to an empty array
@ -19833,25 +19706,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
JSON_THROW(type_error::create(305, "cannot use operator[] with a numeric argument with " + std::string(type_name()), *this));
}
/*!
@brief access specified array element
Returns a const reference to the element at specified location @a idx.
@param[in] idx index of the element to access
@return const reference to the element at index @a idx
@throw type_error.305 if the JSON value is not an array; in that case,
using the [] operator with an index makes no sense.
@complexity Constant.
@liveexample{The example below shows how array elements can be read using
the `[]` operator.,operatorarray__size_type_const}
@since version 1.0.0
*/
/// @brief access specified array element
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
const_reference operator[](size_type idx) const
{
// const operator[] only works for arrays
@ -19863,33 +19719,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
JSON_THROW(type_error::create(305, "cannot use operator[] with a numeric argument with " + std::string(type_name()), *this));
}
/*!
@brief access specified object element
Returns a reference to the element at with specified key @a key.
@note If @a key is not found in the object, then it is silently added to
the object and filled with a `null` value to make `key` a valid reference.
In case the value was `null` before, it is converted to an object.
@param[in] key key of the element to access
@return reference to the element at key @a key
@throw type_error.305 if the JSON value is not an object or null; in that
cases, using the [] operator with a key makes no sense.
@complexity Logarithmic in the size of the container.
@liveexample{The example below shows how object elements can be read and
written using the `[]` operator.,operatorarray__key_type}
@sa see @ref at(const typename object_t::key_type&) for access by reference
with range checking
@sa see @ref value() for access by value with a default value
@since version 1.0.0
*/
/// @brief access specified object element
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
reference operator[](const typename object_t::key_type& key)
{
// implicitly convert null value to an empty object
@ -19909,36 +19740,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
JSON_THROW(type_error::create(305, "cannot use operator[] with a string argument with " + std::string(type_name()), *this));
}
/*!
@brief read-only access specified object element
Returns a const reference to the element at with specified key @a key. No
bounds checking is performed.
@warning If the element with key @a key does not exist, the behavior is
undefined.
@param[in] key key of the element to access
@return const reference to the element at key @a key
@pre The element with key @a key must exist. **This precondition is
enforced with an assertion.**
@throw type_error.305 if the JSON value is not an object; in that case,
using the [] operator with a key makes no sense.
@complexity Logarithmic in the size of the container.
@liveexample{The example below shows how object elements can be read using
the `[]` operator.,operatorarray__key_type_const}
@sa see @ref at(const typename object_t::key_type&) for access by reference
with range checking
@sa see @ref value() for access by value with a default value
@since version 1.0.0
*/
/// @brief access specified object element
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
const_reference operator[](const typename object_t::key_type& key) const
{
// const operator[] only works for objects
@ -19951,33 +19754,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
JSON_THROW(type_error::create(305, "cannot use operator[] with a string argument with " + std::string(type_name()), *this));
}
/*!
@brief access specified object element
Returns a reference to the element at with specified key @a key.
@note If @a key is not found in the object, then it is silently added to
the object and filled with a `null` value to make `key` a valid reference.
In case the value was `null` before, it is converted to an object.
@param[in] key key of the element to access
@return reference to the element at key @a key
@throw type_error.305 if the JSON value is not an object or null; in that
cases, using the [] operator with a key makes no sense.
@complexity Logarithmic in the size of the container.
@liveexample{The example below shows how object elements can be read and
written using the `[]` operator.,operatorarray__key_type}
@sa see @ref at(const typename object_t::key_type&) for access by reference
with range checking
@sa see @ref value() for access by value with a default value
@since version 1.1.0
*/
/// @brief access specified object element
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
template<typename T>
JSON_HEDLEY_NON_NULL(2)
reference operator[](T* key)
@ -19999,36 +19777,8 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
JSON_THROW(type_error::create(305, "cannot use operator[] with a string argument with " + std::string(type_name()), *this));
}
/*!
@brief read-only access specified object element
Returns a const reference to the element at with specified key @a key. No
bounds checking is performed.
@warning If the element with key @a key does not exist, the behavior is
undefined.
@param[in] key key of the element to access
@return const reference to the element at key @a key
@pre The element with key @a key must exist. **This precondition is
enforced with an assertion.**
@throw type_error.305 if the JSON value is not an object; in that case,
using the [] operator with a key makes no sense.
@complexity Logarithmic in the size of the container.
@liveexample{The example below shows how object elements can be read using
the `[]` operator.,operatorarray__key_type_const}
@sa see @ref at(const typename object_t::key_type&) for access by reference
with range checking
@sa see @ref value() for access by value with a default value
@since version 1.1.0
*/
/// @brief access specified object element
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
template<typename T>
JSON_HEDLEY_NON_NULL(2)
const_reference operator[](T* key) const
@ -22883,153 +22633,29 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
/// @name JSON Pointer functions
/// @{
/*!
@brief access specified element via JSON Pointer
Uses a JSON pointer to retrieve a reference to the respective JSON value.
No bound checking is performed. Similar to @ref operator[](const typename
object_t::key_type&), `null` values are created in arrays and objects if
necessary.
In particular:
- If the JSON pointer points to an object key that does not exist, it
is created an filled with a `null` value before a reference to it
is returned.
- If the JSON pointer points to an array index that does not exist, it
is created an filled with a `null` value before a reference to it
is returned. All indices between the current maximum and the given
index are also filled with `null`.
- The special value `-` is treated as a synonym for the index past the
end.
@param[in] ptr a JSON pointer
@return reference to the element pointed to by @a ptr
@complexity Constant.
@throw parse_error.106 if an array index begins with '0'
@throw parse_error.109 if an array index was not a number
@throw out_of_range.404 if the JSON pointer can not be resolved
@liveexample{The behavior is shown in the example.,operatorjson_pointer}
@since version 2.0.0
*/
/// @brief access specified element via JSON Pointer
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
reference operator[](const json_pointer& ptr)
{
return ptr.get_unchecked(this);
}
/*!
@brief access specified element via JSON Pointer
Uses a JSON pointer to retrieve a reference to the respective JSON value.
No bound checking is performed. The function does not change the JSON
value; no `null` values are created. In particular, the special value
`-` yields an exception.
@param[in] ptr JSON pointer to the desired element
@return const reference to the element pointed to by @a ptr
@complexity Constant.
@throw parse_error.106 if an array index begins with '0'
@throw parse_error.109 if an array index was not a number
@throw out_of_range.402 if the array index '-' is used
@throw out_of_range.404 if the JSON pointer can not be resolved
@liveexample{The behavior is shown in the example.,operatorjson_pointer_const}
@since version 2.0.0
*/
/// @brief access specified element via JSON Pointer
/// @sa https://json.nlohmann.me/api/basic_json/operator%5B%5D/
const_reference operator[](const json_pointer& ptr) const
{
return ptr.get_unchecked(this);
}
/*!
@brief access specified element via JSON Pointer
Returns a reference to the element at with specified JSON pointer @a ptr,
with bounds checking.
@param[in] ptr JSON pointer to the desired element
@return reference to the element pointed to by @a ptr
@throw parse_error.106 if an array index in the passed JSON pointer @a ptr
begins with '0'. See example below.
@throw parse_error.109 if an array index in the passed JSON pointer @a ptr
is not a number. See example below.
@throw out_of_range.401 if an array index in the passed JSON pointer @a ptr
is out of range. See example below.
@throw out_of_range.402 if the array index '-' is used in the passed JSON
pointer @a ptr. As `at` provides checked access (and no elements are
implicitly inserted), the index '-' is always invalid. See example below.
@throw out_of_range.403 if the JSON pointer describes a key of an object
which cannot be found. See example below.
@throw out_of_range.404 if the JSON pointer @a ptr can not be resolved.
See example below.
@exceptionsafety Strong guarantee: if an exception is thrown, there are no
changes in the JSON value.
@complexity Constant.
@since version 2.0.0
@liveexample{The behavior is shown in the example.,at_json_pointer}
*/
/// @brief access specified element via JSON Pointer
/// @sa https://json.nlohmann.me/api/basic_json/at/
reference at(const json_pointer& ptr)
{
return ptr.get_checked(this);
}
/*!
@brief access specified element via JSON Pointer
Returns a const reference to the element at with specified JSON pointer @a
ptr, with bounds checking.
@param[in] ptr JSON pointer to the desired element
@return reference to the element pointed to by @a ptr
@throw parse_error.106 if an array index in the passed JSON pointer @a ptr
begins with '0'. See example below.
@throw parse_error.109 if an array index in the passed JSON pointer @a ptr
is not a number. See example below.
@throw out_of_range.401 if an array index in the passed JSON pointer @a ptr
is out of range. See example below.
@throw out_of_range.402 if the array index '-' is used in the passed JSON
pointer @a ptr. As `at` provides checked access (and no elements are
implicitly inserted), the index '-' is always invalid. See example below.
@throw out_of_range.403 if the JSON pointer describes a key of an object
which cannot be found. See example below.
@throw out_of_range.404 if the JSON pointer @a ptr can not be resolved.
See example below.
@exceptionsafety Strong guarantee: if an exception is thrown, there are no
changes in the JSON value.
@complexity Constant.
@since version 2.0.0
@liveexample{The behavior is shown in the example.,at_json_pointer_const}
*/
/// @brief access specified element via JSON Pointer
/// @sa https://json.nlohmann.me/api/basic_json/at/
const_reference at(const json_pointer& ptr) const
{
return ptr.get_checked(this);