launchdarkly::Value Class Reference

#include <value.hpp>

Classes
class	Array
class	Object

Public Types
enum class	Type {   kNull , kBool , kNumber , kString ,   kObject , kArray }

Public Member Functions
	Value (char const *str)
	Value ()
	Value (Value const &val)=default
	Value (Value &&)=default
Value &	operator= (Value const &)=default
Value &	operator= (Value &&)=default
	Value (bool boolean)
	Value (double num)
	Value (int num)
	Value (std::string str)
	Value (std::vector< Value > arr)
	Value (Array arr)
	Value (Object obj)
	Value (std::map< std::string, Value > obj)
	Value (std::initializer_list< Value > values)
	Value (std::optional< std::string > opt_string)
Type	Type () const
bool	IsNull () const
bool	IsBool () const
bool	IsNumber () const
bool	IsString () const
bool	IsArray () const
bool	IsObject () const
bool	AsBool () const
int	AsInt () const
double	AsDouble () const
std::string const &	AsString () const
Array const &	AsArray () const
Object const &	AsObject () const
	operator bool () const
	operator std::string () const
	operator double () const
	operator int () const

Static Public Member Functions
static Value const &	Null ()

Friends
std::ostream &	operator<< (std::ostream &out, Value const &value)

Detailed Description

Value represents any of the data types supported by JSON, all of which can be used for a LaunchDarkly feature flag variation, or for an attribute in an evaluation context. Value instances are immutable.

Uses of JSON types in LaunchDarkly

LaunchDarkly feature flags can have variations of any JSON type other than null. If you want to evaluate a feature flag in a general way that does not have expectations about the variation type, or if the variation value is a complex data structure such as an array or object, you can use the SDK method launchdarkly::client_side::IClient::JsonVariation.

Similarly, attributes of an evaluation context (launchdarkly::Context) can have variations of any JSON type other than null. If you want to set a context attribute in a general way that will accept any type, or set the attribute value to a complex data structure such as an array or object, you can use the builder method launchdarkly::AttributesBuilder< BuilderReturn, BuildType >::set.

Arrays and objects have special meanings in LaunchDarkly flag evaluation:

• An array of values means "try to match any of these values to the targeting rule."
• An object allows you to match a property within the object to the targeting rule. For instance, in the example above, a targeting rule could reference /objectAttr1/color to match the value "green". Nested property references like /objectAttr1/address/street are allowed if a property contains another JSON object.

Constructor & Destructor Documentation

Value() [1/10]

launchdarkly::Value::Value

(

char const *

str

)

Create a Value from a string constant.

Parameters

str	The string constant to base the value on.

Value() [2/10]

launchdarkly::Value::Value

(

)

Construct a value representing null.

Value() [3/10]

launchdarkly::Value::Value

(

bool

boolean

)

Construct a boolean value.

Parameters

boolean

Value() [4/10]

launchdarkly::Value::Value

(

double

num

)

Construct a number value from a double.

Parameters

num

Value() [5/10]

launchdarkly::Value::Value

(

int

num

)

Construct a number value from an integer.

Parameters

num

Value() [6/10]

launchdarkly::Value::Value

(

std::string

str

)

Construct a string value.

Parameters

str

Value() [7/10]

launchdarkly::Value::Value

(

std::vector< Value >

arr

)

Construct an array value from a vector of Value.

Parameters

arr

Value() [8/10]

launchdarkly::Value::Value

(

std::map< std::string, Value >

obj

)

Construct an object value from a map of Value.

Parameters

obj

Value() [9/10]

launchdarkly::Value::Value

(

std::initializer_list< Value >

values

)

Create an array type value from the given list.

Cannot be used to create object type values.

Parameters

values

Value() [10/10]

launchdarkly::Value::Value

(

std::optional< std::string >

opt_string

)

Create either a value string, or null value, from an optional string.

Parameters

opt_string

Member Function Documentation

AsArray()

Value::Array const & launchdarkly::Value::AsArray

(

)

const

If the value is an array type, then return a reference to that array as a vector, otherwise return a reference to an empty vector.

Returns

The value as a vector, or an empty vector.

AsBool()

bool launchdarkly::Value::AsBool

(

)

const

If the value is a boolean, then return the boolean, otherwise return false.

Returns

The value of the boolean, or false.

AsInt()

int launchdarkly::Value::AsInt

(

)

const

If the value is a number, then return the internal double value as an integer, otherwise return 0.

Returns

The value as an integer, or 0.

AsObject()

Value::Object const & launchdarkly::Value::AsObject

(

)

const

if the value is an object type, then return a reference to that object as a map, otherwise return a reference to an empty map.

Returns

The value as a map, or an empty map.

AsString()

std::string const & launchdarkly::Value::AsString

(

)

const

If the value is a string, then return a reference to that string, otherwise return a reference to an empty string.

Returns

The value as a string, or an empty string.

IsArray()

bool launchdarkly::Value::IsArray

(

)

const

Returns true if the value is an array.

Returns

True if the value is an array.

IsBool()

bool launchdarkly::Value::IsBool

(

)

const

Returns true if the value is a boolean.

Returns

IsNull()

bool launchdarkly::Value::IsNull

(

)

const

Returns true if the value is a null.

Unlike other variants there is not an as_null(). Instead use the return value from this function as a marker.

Returns

True if the value is null.

IsNumber()

bool launchdarkly::Value::IsNumber

(

)

const

Returns true if the value is a number.

Numbers are always stored as doubles, but can be accessed as either an int or double for convenience.

Returns

True if the value is a number.

IsObject()

bool launchdarkly::Value::IsObject

(

)

const

Returns true if the value is an object.

Returns

True if the value is an object.

IsString()

bool launchdarkly::Value::IsString

(

)

const

Returns true if the value is a string.

Returns

True if the value is a string.

Null()

Value const & launchdarkly::Value::Null ( )

static

Get a null value.

Returns

The null value.

Type()

enum Value::Type launchdarkly::Value::Type

(

)

const

Get the type of the attribute.

---

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

• /home/runner/work/cpp-sdks/cpp-sdks/libs/common/include/launchdarkly/value.hpp
• /home/runner/work/cpp-sdks/cpp-sdks/libs/common/src/value.cpp