Generic data type. More...

#include <parsnip.h>

Data Structures
union	data_t

struct	dictionary_t

struct	iterator
	An iterator used to walk items in Data's lists. More...

struct	list_t

Public Types
enum class	Type { Null , Dictionary , List , String , FlexibleString , Integer , Real , Boolean }
	Types that may be stored in the data. More...

using	StringType = std::string

using	ListType = std::vector< Data >

using	size_type = ListType::size_type

Public Member Functions
	Data (std::nullptr_t null=nullptr)
	Default constructor.

	Data (const char *value, bool type_certainty=true)
	String constructor.

	Data (const std::string &value, bool type_certainty=true)
	String constructor, accepting C++ string.

template<typename T , typename = typename std::enable_if<!std::is_same<T, bool>::value && std::is_integral<T>::value, int>::type>
	Data (T value) noexcept
	Integer constructor.

	Data (double value) noexcept
	Floating point constructor.

	Data (bool value) noexcept
	Boolean constructor.

template<typename... T>
	Data (dictionary_t, T... params)
	Dictionary constructor.

template<typename... T>
	Data (list_t, T... params)
	List constructor.

	Data (Data &&from) noexcept
	Move construction.

Data &	operator= (Data &&from) noexcept
	Move assignment.

	Data (const Data &from)
	Copy constructor.

Data &	operator= (const Data &from)
	Copy assignment.

bool	operator== (const Data &compare) const
	Compare two structures.

bool	operator!= (const Data &compare) const

const Data &	makeFlexible () const
	IF a data item is a string, change it to a flexible string.

bool	isNull (void) const noexcept
	Check if data contains a value.

const StringType &	asString () const
	Retrieve string value.

long	asLong (int base=0) const
	Return value of data as a long integer.

int	asInteger (int base=0) const
	Return value of data as an integer.

double	asDouble () const
	Return value of data as a double. If the data is a string, parse it as a float.

bool	asBoolean () const
	Return value of data as a boolean. If the data is a string, translate "true" and "false".

ListType	asList () const
	Return data as a list.

template<typename DataType , typename = typename std::enable_if<std::is_same<DataType, std::string>::value>::type>
const std::string &	as () const
	Extract data as a string (templated version).

template<typename DataType , typename = typename std::enable_if<!std::is_same<DataType, bool>::value && std::is_integral<DataType>::value>::type>
DataType	as (int base=0) const
	Extract data as an integer type, except boolean.

template<typename DataType , typename = typename std::enable_if<std::is_floating_point<DataType>::value>::type>
DataType	as () const
	Extract data as a floating point type.

template<typename DataType , typename = typename std::enable_if<std::is_same<DataType, bool>::value>::type>
bool	as () const
	Extract data as a boolean.

template<typename DataType , typename = typename std::enable_if<std::is_same<DataType, Data>::value>::type>
const Data &	as () const
	Retrieve data as the object itself.

template<typename Container , typename = typename std::enable_if<std::is_class<Container>::value && !std::is_same<Container, Data>::value && !std::is_same<Container, std::string>::value>::type>
Container	as (std::nullptr_t null=nullptr) const
	Return contents of a list as a specific datatype.

template<typename Datatype >
Datatype	getOr (const std::string &name, const Datatype &defvalue) const
	Extract a value if a member exists, otherwise use a default.

StringType	getOr (const std::string &name, const char *defvalue) const
	Specialization of 'getOr' that accepts a const char * default; otherwise, overload resolution chooses implicit instantiation of a Data and uses that as a default rather than implicitly instantiating the string type.

Data	getOr (const std::string &name, const Data &defvalue) const
	Specialization of `getOr` for `Data`.

template<typename Datatype >
std::vector< Datatype >	toList () const
	Return a list or a single item in a container.

const Data &	operator[] (const std::string &word) const
	Dictionary member accessor.

Data &	operator[] (const std::string &word)
	Dictionary member accessor.

bool	contains (const std::string &word) const
	Check if a key exists in a dictionary.

void	remove (const std::string &word)
	Remove key from dictionary.

const Data &	at (const std::string &word) const

template<typename DataType , typename = typename std::enable_if<std::is_trivial<DataType>::value>::type>
void	foreach (std::function< void(const std::string &, DataType)> func) const
	Iterate over all dictionary members, calling a function with each key and value.

template<typename DataType >
void	foreach (std::function< void(const std::string &, const DataType &)> func) const
	Specialization of dictionary iterator for strings and `Data`.

const Data &	operator[] (size_type index) const
	List member accessor.

Data &	operator[] (size_type index)
	List member accessor.

void	remove (size_type index)
	Remove entry from position in list.

void	push_back (const Data &value)
	List back-inserter.

void	push_back (Data &&value)
	List back-inserter.

size_type	size () const
	Retrieve number of entries in a list.

bool	empty () const
	Empty check.

template<typename DataType , typename = typename std::enable_if<std::is_trivial<Type>::value>::type>
void	foreach (std::function< void(const DataType)> func) const
	Iterate over all list members, calling a function with each value.

template<typename DataType >
void	foreach (std::function< void(const DataType &)> func) const
	Specialization of list iterator for strings and `Data`.

Data::iterator	begin () const
	Retrieve forward iterator.

Data::iterator	end () const
	Retrieve end iterator.

std::string	toJson (int indent=NoIndent) const
	Return serial data encoded using JSON.

std::ostream &	toJson (std::ostream &target, int indent=NoIndent, bool suppress=false) const
	Write serial data encoded using JSON.

std::ostream &	dumpJson (const std::string &intro, std::ostream &target=std::clog) const

Static Public Member Functions
static const char *	type_name (Type ty)
	Return the name corresponding to a type.

template<typename T = Data>
static Data	make_dictionary (std::initializer_list< std::pair< const char *, const T > > initial_data)
	Dictionary factory.

template<typename... T>
static Data	make_list (T &&... params)
	List factory.

Static Public Attributes
static const struct Parsnip::Data::dictionary_t	Dictionary
	Dictionary flag type/value.

static const struct Parsnip::Data::list_t	List
	List flag type/value.

static constexpr bool	Flexible {false}
	Flag to make strings flexible.

static constexpr int	NoIndent {-32767}
	Prevent indentation.

Protected Types
using	DictionaryType = std::unordered_map< std::string, Data >

Protected Member Functions
void	release ()
	Release any stored data and restore to an "empty" state.

Protected Attributes
Type	datatype = Type::Null
	Type presently stored in object.

union Parsnip::Data::data_t	data

Friends
class	IncorrectDataType

class	SchemaBase

class	DictionarySchema

class	ConjunctionSchema

Detailed Description

Generic data type.

A datatype that can hold strings, numbers, booleans, lists, or dictionaries.

Member Enumeration Documentation

◆ Type

enum class Parsnip::Data::Type

strong

Types that may be stored in the data.

Enumerator
Null	Nothing is present.
List	Dictionary keyed by string.
String	The value is string, even if the string contains a number.
FlexibleString	The value is a string, but may convert to a number if the value is numeric.
Integer	Value is an integer but may also be accessed as a real.

Constructor & Destructor Documentation

◆ Data() [1/3]

Parsnip::Data::Data	(	const char *	value,
		bool	type_certainty = `true`
	)

inline

String constructor.

Parameters

value	The string value to assign.
type_certainty	True if known to be string, false if it may be a number or boolean in string form.

◆ Data() [2/3]

template<typename... T>

Parsnip::Data::Data	(	dictionary_t	,
		T...	params
	)

inline

Dictionary constructor.

Use Dictionary flag variable as first parameter. Subsequent parameters are name, value ... pairs (function must have an odd number of arguments).

◆ Data() [3/3]

template<typename... T>

Parsnip::Data::Data	(	list_t	,
		T...	params
	)

inline

List constructor.

Use List flag variable as first parameter. Subsequent parameters are inserted in order as list members.

Member Function Documentation

◆ as() [1/6]

template<typename DataType , typename = typename std::enable_if<std::is_same<DataType, std::string>::value>::type>

const std::string & Parsnip::Data::as ( ) const

inline

Extract data as a string (templated version).

Exceptions

IncorrectDataType if value is not a string.

◆ as() [2/6]

template<typename DataType , typename = typename std::enable_if<std::is_floating_point<DataType>::value>::type>

DataType Parsnip::Data::as ( ) const

inline

Extract data as a floating point type.

Template Parameters

DataType the desired return type.

Exceptions

DataRangeError	if value will not fit `DataType`.
IncorrectDataType	if value is not a number.

◆ as() [3/6]

template<typename DataType , typename = typename std::enable_if<std::is_same<DataType, bool>::value>::type>

bool Parsnip::Data::as ( ) const

inline

Extract data as a boolean.

Exceptions

IncorrectDataType if value is not true or false.

◆ as() [4/6]

template<typename DataType , typename = typename std::enable_if<std::is_same<DataType, Data>::value>::type>

const Data & Parsnip::Data::as ( ) const

inline

Retrieve data as the object itself.

Seems stupid on the surface, but useful for templates.

◆ as() [5/6]

template<typename DataType , typename = typename std::enable_if<!std::is_same<DataType, bool>::value && std::is_integral<DataType>::value>::type>

DataType Parsnip::Data::as ( int base = 0 ) const

inline

Extract data as an integer type, except boolean.

Template Parameters

DataType the desired return type.

Exceptions

DataRangeError	if value will not fit in `DataType`.
IncorrectDataType	if value is not an integer.

◆ as() [6/6]

template<typename Container , typename = typename std::enable_if<std::is_class<Container>::value && !std::is_same<Container, Data>::value && !std::is_same<Container, std::string>::value>::type>

Container Parsnip::Data::as ( std::nullptr_t null = nullptr ) const

inline

Return contents of a list as a specific datatype.

Template Parameters

Container A standard (-like) container, such as std::vector <std::string>, std::list <int>, or even std::vector<std::vector<long>> to extract a contents of a 2-dimensional array. Member typedef Container::value_type determines the inner type.

Exceptions

IncorrectDataType if the item is not a list, or any of the list's members are not the expected type.

◆ asInteger()

int Parsnip::Data::asInteger ( int base = 0 ) const

Return value of data as an integer.

See also: asLong().

Parameters

base	The base for interpreting strings. Default is 10.

Returns: The integer.

Exceptions

DataRangeError if the value is out of representable range.

◆ asList()

Data::ListType Parsnip::Data::asList ( ) const

Return data as a list.

Null data is returned as an empty list.
Lists return a copy of their elements.
Individual elements are wrapped in a 1-element list.
Exceptions

IncorrectDataType for dictionaries.

◆ asLong()

long Parsnip::Data::asLong ( int base = 0 ) const

Return value of data as a long integer.

If the data is a string, parse it as an integer.

Parameters

base	The base for interpreting strings. Default is 10.

Returns: The long integer.

Exceptions

DataRangeError if the value is out of representable range.

◆ asString()

const Data::StringType & Parsnip::Data::asString ( ) const

Retrieve string value.

Returns: String value.

Exceptions

IncorrectDataType if value is not a string.

◆ begin()

Data::iterator Parsnip::Data::begin ( ) const

inline

Retrieve forward iterator.

Returns: Forward iterator positioned at first element.

Exceptions

IncorrectDataType if not a list.

◆ contains()

bool Parsnip::Data::contains ( const std::string & key ) const

Check if a key exists in a dictionary.

Parameters

key	The key to check.

Returns: True if present in dictionary, false otherwise.

◆ empty()

bool Parsnip::Data::empty ( ) const

inline

Empty check.

Use isNull to check specifically for that condition.

Returns: True for null type, or lists or dictionaries that are empty.

◆ end()

Data::iterator Parsnip::Data::end ( ) const

inline

Retrieve end iterator.

Returns: Forward iterator positioned after last element.

Exceptions

IncorrectDataType if not a list.

◆ foreach() [1/2]

template<typename DataType , typename = typename std::enable_if<std::is_trivial<Type>::value>::type>

void Parsnip::Data::foreach ( std::function< void(const DataType)> func ) const

inline

Iterate over all list members, calling a function with each value.

This implementation covers simple types.

Template Parameters

DataType The datatype expected to be in the dictionary.

Parameters

func	The function to invoke with each member.

Exceptions

IncorrectDataType if the list contains values of inapplicable type. This occurs when encountered; some invokations may happen before throwing.

◆ foreach() [2/2]

template<typename DataType , typename = typename std::enable_if<std::is_trivial<DataType>::value>::type>

void Parsnip::Data::foreach ( std::function< void(const std::string &, DataType)> func ) const

inline

Iterate over all dictionary members, calling a function with each key and value.

This implementation covers simple types.

Template Parameters

DataType The datatype expected to be in the dictionary.

Parameters

func	The function to invoke with each member.

Exceptions

IncorrectDataType if the dictionary contains values of inapplicable type. This occurs when encountered; some invokations may happen before throwing.

◆ getOr() [1/2]

Data Parsnip::Data::getOr	(	const std::string &	name,
		const Data &	defvalue
	)		const

inline

Specialization of getOr for Data.

Template Parameters

Datatype The desired return type of the data.

Parameters

name	The name of the member to retrieve.
defvalue	The default to use if the member is not present.

Exceptions

IncorrectDataType if the object is not a dictionary.

◆ getOr() [2/2]

template<typename Datatype >

Datatype Parsnip::Data::getOr	(	const std::string &	name,
		const Datatype &	defvalue
	)		const

inline

Extract a value if a member exists, otherwise use a default.

Template Parameters

Datatype The desired return type of the data.

Parameters

name	The name of the member to retrieve.
defvalue	The default to use if the member is not present.

Exceptions

IncorrectDataType if the object is not a dictionary, or the item is present but not the desired type.

◆ isNull()

bool Parsnip::Data::isNull ( void ) const

inlinenoexcept

Check if data contains a value.

Returns: True if empty, false otherwise.

◆ make_dictionary()

template<typename T = Data>

static Data Parsnip::Data::make_dictionary ( std::initializer_list< std::pair< const char *, const T > > initial_data )

inlinestatic

Dictionary factory.

Parameters

initial_data Name-value pairs to be inserted into the dictionary.

Warning: Initializer lists cannot use rvalue references; hence, elements are copied. This is fine for simple items, but should be avoided when inserting complicatated structures. Prefer move assignment or Parsnip::Data (Parsnip::Data::Dictionary, ...).

◆ make_list()

template<typename... T>

static Data Parsnip::Data::make_list ( T &&... params )

inlinestatic

List factory.

Parameters are inserted in order as list members.

◆ makeFlexible()

const Data & Parsnip::Data::makeFlexible ( ) const

IF a data item is a string, change it to a flexible string.

Use of this function should be very rare; strings should be strings and numbers numbers. But if a number gets stored in a string, this allows it to be accessed until it can be fixed (and it tolerates fixing, too).

◆ operator==()

bool Parsnip::Data::operator== ( const Data & compare ) const

Compare two structures.

Parameters

compare The structure to compare to.

Returns: True if identical, false otherwise.

◆ operator[]() [1/4]

Data & Parsnip::Data::operator[] ( const std::string & key )

Dictionary member accessor.

If dictionary is NOT constant, accessing non-existent key creates it.

◆ operator[]() [2/4]

const Data & Parsnip::Data::operator[] ( const std::string & key ) const

Dictionary member accessor.

If dictionary is constant, avoid automatic insertion, and throw error if key is not present in dictionary.

◆ operator[]() [3/4]

Data & Parsnip::Data::operator[] ( size_type index )

List member accessor.

If list is NOT constant, accessing outside of range expands list size

◆ operator[]() [4/4]

const Data & Parsnip::Data::operator[] ( size_type index ) const

List member accessor.

If list is constant, avoid automatic insertion, and throw error if index is out of range.

◆ size()

Data::size_type Parsnip::Data::size ( ) const

Retrieve number of entries in a list.

Returns: Count of values in list.

Exceptions

IncorrectDataType if not a list.

◆ toJson() [1/2]

std::string Parsnip::Data::toJson ( int indent = NoIndent ) const

Return serial data encoded using JSON.

Parameters

indent Starting indentation for elements.

Returns: A string.

◆ toJson() [2/2]

std::ostream & Parsnip::Data::toJson	(	std::ostream &	target,
		int	indent = `NoIndent`,
		bool	suppress = `false`
	)		const

Write serial data encoded using JSON.

Parameters

target	Stream to which to write data.
indent	Starting indentation for elements.
suppress	If true, suppress indent on first line.

Returns: The output stream.

◆ toList()

template<typename Datatype >

std::vector< Datatype > Parsnip::Data::toList ( ) const

inline

Return a list or a single item in a container.

Template Parameters

Container A standard (-like) container, such as std::vector <std::string>. Member typedef Container::value_type determines the inner type. If this object is a list, the container is populated with the list contents; otherwise, it is populated with the single data item.

Exceptions

IncorrectDataType if this object is neither a list nor the expected type, or if it is a list but some members are not the expected type.

◆ type_name()

const char * Parsnip::Data::type_name ( Type ty )

static

Return the name corresponding to a type.

Parameters

ty	The type whose name to retrieve.

Returns: The name of the type.

The documentation for this class was generated from the following files:

parsnip/parsnip.h
parsnip/parsnip_json.cpp
parsnip/parsnip_types.cpp

Data Structures

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Protected Types

Protected Member Functions

Protected Attributes

Friends

Detailed Description

Member Enumeration Documentation

◆ Type

Constructor & Destructor Documentation

◆ Data() [1/3]

◆ Data() [2/3]

◆ Data() [3/3]

Member Function Documentation

◆ as() [1/6]

◆ as() [2/6]

◆ as() [3/6]

◆ as() [4/6]

◆ as() [5/6]

◆ as() [6/6]

◆ asInteger()

◆ asList()

◆ asLong()

◆ asString()

◆ begin()

◆ contains()

◆ empty()

◆ end()

◆ foreach() [1/2]

◆ foreach() [2/2]

◆ getOr() [1/2]

◆ getOr() [2/2]

◆ isNull()

◆ make_dictionary()

◆ make_list()

◆ makeFlexible()

◆ operator==()

◆ operator[]() [1/4]

◆ operator[]() [2/4]

◆ operator[]() [3/4]

◆ operator[]() [4/4]

◆ size()

◆ toJson() [1/2]

◆ toJson() [2/2]

◆ toList()

◆ type_name()