boost::logic::tribool Class Reference

A 3-state boolean type. More...

#include <tribool.hpp>

Public Types
enum	value_t {   false_value,   true_value,   indeterminate_value }
	The actual stored value in this 3-state boolean, which may be false, true, or indeterminate. More...

Public Member Functions
	tribool ()
	Construct a new 3-state boolean value with the value 'false'. More...
	tribool (bool initial_value)
	Construct a new 3-state boolean value with the given boolean value, which may be true or false. More...
	tribool (indeterminate_keyword_t)
	Construct a new 3-state boolean value with an indeterminate value. More...
	operator safe_bool () const
	Use a 3-state boolean in a boolean context. More...

Public Attributes
enum boost::logic::tribool::value_t	value

Detailed Description

A 3-state boolean type.

3-state boolean values are either true, false, or indeterminate.

Member Enumeration Documentation

enum boost::logic::tribool::value_t

The actual stored value in this 3-state boolean, which may be false, true, or indeterminate.

Enumerator
false_value
true_value
indeterminate_value

Constructor & Destructor Documentation

boost::logic::tribool::tribool ( )

inline

Construct a new 3-state boolean value with the value 'false'.

Exceptions

nothrow

boost::logic::tribool::tribool ( bool  initial_value )

inline

Construct a new 3-state boolean value with the given boolean value, which may be true or false.

Exceptions

nothrow

boost::logic::tribool::tribool ( indeterminate_keyword_t  )

inline

Construct a new 3-state boolean value with an indeterminate value.

Exceptions

nothrow

Member Function Documentation

boost::logic::tribool::operator safe_bool ( ) const

inline

Use a 3-state boolean in a boolean context.

Will evaluate true in a boolean context only when the 3-state boolean is definitely true.

Returns

true if the 3-state boolean is true, false otherwise

Exceptions

nothrow

References true_value, and value.

Member Data Documentation

enum boost::logic::tribool::value_t boost::logic::tribool::value

Referenced by boost::logic::indeterminate(), operator safe_bool(), and boost::logic::operator!().

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

• boost_1_57_0/boost/logic/tribool.hpp