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5352856f04
* Add key_compare member to ordered_map
* Replace == with key_compare in ordered_map
* Expose the actual comparison function used by object_t
nlohmann::ordered_map uses a different comparison function than the one
provided via template parameter.
* Introduce a type trait to detect if object_t has a key_compare member.
* Rename object_comparator_t to default_object_comparator_t.
* Add object_comparator_t to be conditionally defined as
object_t::key_compare, if available, or default_object_comparator_t
otherwise.
* Update the documentation accordingly.
Co-authored-by: Niels Lohmann <niels.lohmann@gmail.com>
* Add type traits to check if a type is usable as object key
Add type trait to check:
* if a type is a specialization of a template.
* if a type is a json_pointer.
* if a type is a basic_json::{const_,}iterator.
* if two types are comparable using a given comparison functor.
* if a type is comparable to basic_json::object_t::key_type.
* if a type has a member type is_transparent.
* if a type is usable as object key.
* if a type has an erase() function accepting a given KeyType.
Co-authored-by: Niels Lohmann <niels.lohmann@gmail.com>
* Rework basic_json element access to accept more key types
Rework basic_json element access member functions and operators to
accept any type that meets the requirements defined by type trait
detail::is_usable_as_key_type.
Member functions and operators:
* at()
* operator[]
* value()
* erase()
* find()
* count()
* contains()
Update documentation to reflect these changes.
Add unit tests to excercise the new functions using std::string_view.
Co-authored-by: Niels Lohmann <niels.lohmann@gmail.com>
Co-authored-by: Niels Lohmann <niels.lohmann@gmail.com>
1.9 KiB
1.9 KiB
nlohmann::basic_json::to_ubjson
// (1)
static std::vector<std::uint8_t> to_ubjson(const basic_json& j,
const bool use_size = false,
const bool use_type = false);
// (2)
static void to_ubjson(const basic_json& j, detail::output_adapter<std::uint8_t> o,
const bool use_size = false, const bool use_type = false);
static void to_ubjson(const basic_json& j, detail::output_adapter<char> o,
const bool use_size = false, const bool use_type = false);
Serializes a given JSON value j to a byte vector using the UBJSON (Universal Binary JSON) serialization format. UBJSON
aims to be more compact than JSON itself, yet more efficient to parse.
- Returns a byte vector containing the UBJSON serialization.
- Writes the UBJSON serialization to an output adapter.
The exact mapping and its limitations is described on a dedicated page.
Parameters
j(in)- JSON value to serialize
o(in)- output adapter to write serialization to
use_size(in)- whether to add size annotations to container types; optional,
#!cpp falseby default. use_type(in)- whether to add type annotations to container types (must be combined with
#!cpp use_size = true); optional,#!cpp falseby default.
Return value
- UBJSON serialization as byte vector
- (none)
Exception safety
Strong guarantee: if an exception is thrown, there are no changes in the JSON value.
Complexity
Linear in the size of the JSON value j.
Examples
??? example
The example shows the serialization of a JSON value to a byte vector in UBJSON format.
```cpp
--8<-- "examples/to_ubjson.cpp"
```
Output:
```json
--8<-- "examples/to_ubjson.output"
```
Version history
- Added in version 3.1.0.