Batteries Included

• Default Traits
• Additional Traits
• Binding Traits
• Events Producers
• Events Consumers
• Events Transformers
• Convenience Functions
• Conversion Utilities

Default Traits

The included Type Traits contain (partial) specialisations for the following types.

Specialised for	Remarks
null_t
bool
signed integers
unsigned integers
double, float
empty_binary_t
empty_array_t
empty_object_t
std::string
tao::string_view
const char*
const std::string&
std::vector< tao::byte >
tao::binary_view
const std::vector< tao::byte >&
std::vector< basic_value< Traits, Base > >	Corresponds to JSON Array.
basic_value< Traits, Base >*	Creates Value Pointer; must not be nullptr.
const basic_value< Traits, Base >*	Creates Value Pointer; must not be nullptr.
std::map< std::string, basic_value< Traits, Base > >	Corresponds to JSON Object.
tao::optional< T >	Empty optional corresponds to JSON Null.

Additional Traits

The following additional specialisations are part of various additional traits classes. These classes are defined in various headers in tao/json/contrib. It is also possible to include tao/json/contrib/traits.hpp which adds appropriate specialisations to the default traits tao::json::traits<>.

Implementation for	Header
std::array< T, N >	tao/json/contrib/array_traits.hpp
std::deque< T >	tao/json/contrib/deque_traits.hpp
std::list< T >	tao/json/contrib/list_traits.hpp
std::map< std::string, T >	tao/json/contrib/map_traits.hpp
std::pair< U, V >	tao/json/contrib/pair_traits.hpp
std::set< T >	tao/json/contrib/set_traits.hpp
std::shared_ptr< T >	tao/json/contrib/shared_ptr_traits.hpp
std::tuple< Ts... >	tao/json/contrib/tuple_traits.hpp
std::unique_ptr< T >	tao/json/contrib/unique_ptr_traits.hpp
std::unordered_map< std::string, T >	tao/json/contrib/unordered_map_traits.hpp
std::unordered_set< T >	tao/json/contrib/unordered_set_traits.hpp
std::vector< T >	tao/json/contrib/vector_traits.hpp

Events Producers

Events Producers are functions that take some input from which they generate Events function calls on a provided Consumer.

The common namespace prefix tao::json:: is omitted.

Producer	Description
events::from_stream	Reads JSON from a std::istream.
events::from_string	Reads JSON from a std::string.
events::from_value	Generates Events for a basic_value<>.
events::from_file	Reads JSON from the file.
jaxn::events::from_stream	Reads JAXN from a std::istream.
jaxn::events::from_string	Reads JAXN from a std::string.
jaxn::events::from_file	Reads JAXN from the file.
cbor::events::from_string	Reads CBOR from a std::string.
cbor::events::from_file	Reads CBOR from the file.
msgpack::events::from_string	Reads MSGPACK from a std::string.
msgpack::events::from_file	Reads MSGPACK from the file.
ubjson::events::from_string	Reads UBJSON from a std::string.
ubjson::events::from_file	Reads UBJSON from the file.

Events Consumers

Events Consumers are structs or classes that implement (a complete subset of) the Events Interface. Consumers are usually instantiated and then passed to an Events Producer function as argument.

The common namespace prefix tao::json:: is omitted.

Consumer	Description
events::debug	Writes all Events to a std::ostream in human-readable form.
events::discard	Does nothing with the Events it receives.
events::hash	Calculates a SHA-256 hash for the received Events.
events::statistics	Counts Events, and string and binary lengths.
events::to_pretty_stream	Writes nicely formatted JSON to a std::ostream.
events::to_stream	Writes compact JSON to a std::ostream.
events::to_string	Writes compact JSON to a std::string.
events::to_value	Builds a Value with the received Events.
events::validate_event_order	Checks whether the order of received Events is consistent.
jaxn::events::to_pretty_stream	Writes nicely formatted JAXN to a std::ostream.
jaxn::events::to_stream	Writes compact JAXN to a std::ostream.
jaxn::events::to_string	Writes compact JAXN to a std::string.
cbor::events::to_stream	Writes CBOR to a std::ostream.
cbor::events::to_string	Writes CBOR to a std::string.
msgpack::events::to_stream	Writes MSGPACK to a std::ostream.
msgpack::events::to_string	Writes MSGPACK to a std::string.
ubjson::events::to_stream	Writes UBJSON to a std::ostream.
ubjson::events::to_string	Writes UBJSON to a std::string.

Events Transformers

Transformers are structs or classes that are both Event Consumers that implement the Events Interface functions, and Event Producers that call the Events Interface functions on one or more other Events Consumers.

The common namespace prefix tao::json:: is omitted.

Transformer	Description
events::binary_to_base64	Passes through all Events except for binary data which is converted to base64-encoded strings.
events::binary_to_base64url	Passes through all Events except for binary data which is converted to URL-safe base64-encoded strings.
events::binary_to_exception	Passes through all Events except for binary data which provokes an exception.
events::binary_to_hex	Passes through all Events except for binary data which is is converted to hex-dumped strings.
events::key_camel_case_to_snake_case	Passes through all Events except for keys in Objects which are converted from "CamelCaseStyle" to "snake_case_style".
events::key_snake_case_to_camel_case	Passes through all Events except for keys in Objects which are converted from "snake_case_style" to "CamelCaseStyle".
events::limit_nesting_depth	Passes through all Events but throws an exception when the nesting of Arrays and Objects exceeds a limit.
events::limit_value_count	Passes through all Events but throws an exception when the total number of (sub)-value exceeds a limit.
events::events::non_finite_to_exception	Passes through all Events except for numbers of type double which contain non-finite values which provoke an exception.
events::non_finite_to_null	Passes through all Events except for numbers of type double which contain non-finite values which are passed on as null().
events::non_finite_to_string	Passes through all Events except for numbers of type double which contain non-finite values which are passed on as appropriate string().
events::prefer_signed	Passes through all Events except for numbers of type std::uint64_t which fit into a std::int64_t and are passed on as such.
events::prefer_unsigned	Passes through all Events except for numbers of type std::int64_t which fit into a std::uint64_t and are passed on as such.
events::ref	Passes all Events to another Consumer or Transformer to which it holds a C++ reference.
events::tee	Passes all Events to an arbitrary number of other Consumers or Transformers which it holds in a std::tuple<>.
events::validate_keys	Passes through all Events except for keys which are first validated against a provided PEGTL grammar rule.
events::virtual_ref	Like ref, but implements the virtual Event functions from virtual_base.

Convenience Functions

Functions that combine the similarly named Events Producer from above with an Events Consumer to return a corresponding Value.

The common namespace prefix tao::json:: is omitted.

Function	Description
from_stream	Reads JSON from a std::istream.
from_string	Reads JSON from a std::string.
from_file	Reads JSON from the file.
jaxn::from_stream	Reads JAXN from a std::istream.
jaxn::from_string	Reads JAXN from a std::string.
jaxn::from_file	Reads JAXN from the file.
cbor::from_string	Reads CBOR from a std::string.
cbor::from_file	Reads CBOR from the file.
msgpack::from_string	Reads MSGPACK from a std::string.
msgpack::from_file	Reads MSGPACK from the file.
ubjson::from_string	Reads UBJSON from a std::string.
ubjson::from_file	Reads UBJSON from the file.

Functions that combine the similarly named Events Consumers with a Producer that generates Events from a Value.

The common namespace prefix tao::json:: is omitted.

Function	Description
to_stream	Writes compact or nicely formatted JSON to a std::ostream.
to_string	Writes compact or nicely formatted JSON to a std::string.
jaxn::to_stream	Writes compact or nicely formatted JAXN to a std::ostream.
jaxn::to_string	Writes compact or nicely formatted JAXN to a std::string.
jaxn::to_stream	Writes CBOR to a std::ostream.
jaxn::to_string	Writes CBOR to a std::string.
msgpack::to_stream	Writes MSGPACK to a std::ostream.
msgpack::to_string	Writes MSGPACK to a std::string.
ubjson::to_stream	Writes UBJSON to a std::ostream.
ubjson::to_string	Writes UBJSON to a std::string.

These functions optionally apply an arbitrary list of Transformers given as additional template parameters.

Conversion Utilities

The following conversion utilities are included in the src/examples/json directory. Note that they convert between formats on-the-fly, i.e. without creating any intermediate in-memory representation.

cbor_to_jaxn
cbor_to_json
cbor_to_msgpack
cbor_to_pretty_jaxn
cbor_to_pretty_json
cbor_to_ubjson
jaxn_to_cbor
jaxn_to_jaxn
jaxn_to_msgpack
jaxn_to_pretty_jaxn
jaxn_to_ubjson
json_to_cbor
json_to_json
json_to_msgpack
json_to_pretty_json
json_to_ubjson
msgpack_to_cbor
msgpack_to_jaxn
msgpack_to_json
msgpack_to_pretty_jaxn
msgpack_to_pretty_json
msgpack_to_ubjson
ubjson_to_cbor
ubjson_to_jaxn
ubjson_to_json
ubjson_to_msgpack
ubjson_to_prety_jaxn
ubjson_to_prety_json

Copyright (c) 2018-2023 Dr. Colin Hirsch and Daniel Frey