xboolean Class Reference

The "extended boolean" class. More...

#include <XBOOL.H>

Inheritance diagram for xboolean:

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Public Types
enum	xbool { Unknown = -1, False = false, True = true }
Public Member Functions
	xboolean (xbool xb=Unknown)
	xboolean (bool b)
	xboolean (const xboolean &xb)
virtual void	CalculateValue (void)
virtual void	CalculateValue (void) const
virtual xbool	GetValue (void)
virtual xbool	GetValue (void) const
virtual wxString	GetValueString (void)
bool	IsFalse (void)
bool	IsTrue (void)
bool	IsUnknown (void)
xboolean	operator! (void)
xboolean &	operator= (const xboolean &xb)
xboolean &	operator= (bool &b)
xboolean	operator== (bool &b)
xboolean	operator!= (xboolean &xb)
xboolean	operator!= (bool &b)
Data Fields
enum xboolean::xbool	value
Friends
xboolean	operator && (xboolean &xbL, xboolean &xbR)
xboolean	operator && (bool &bL, xboolean &xbR)
xboolean	operator && (xboolean &xbL, bool &bR)
xboolean	operator|| (xboolean &xbL, xboolean &xbR)
xboolean	operator|| (bool &bL, xboolean &xbR)
xboolean	operator|| (xboolean &xbL, bool &bR)
xboolean	operator== (xboolean &xbL, xboolean &xbR)

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Detailed Description

The "extended boolean" class.

This class implements the special kind "extended boolean". It extends the usual "boolean" class with value and functionality "unknown" and defines logical constans and operations. It is upwards compatible with the usual "boolean" class and functionality. The 'extended boolean' class is the anchestor of the 'generic rule' class, but it can also be used alone. The "truth tables" are shown below.

Logical negation (unary).

(NOT) !A	A
	U	F	T
	U	T	F

Logical AND (binary).

(AND) A && B		A
		U	F	T
B	U	U	F	U
	F	F	F	F
	T	U	F	T

Logical OR (binary).

(OR) A || B		A
		U	F	T
B	U	U	U	T
	F	U	F	T
	T	T	T	T

Logical equivalence (binary).

(EQUALS) A == B		A
		U	F	T
B	U	U	U	U
	F	U	T	F
	T	U	F	T

For easier readability, the notations AND, OR, NOT have been introduced and used, both in the source files and the manual, for the logical operators &&, || and !.

Note that the objects wxXXX are parts of the multiplatform package wxWindows, their detailed description is given there.

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Member Enumeration Documentation

enum xboolean::xbool

Defines the allowed values for the 3-state logic. Enumeration values: Unknown  False  True

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Constructor & Destructor Documentation

xboolean::xboolean (  xbool  xb = Unknown  )  [inline]

(default) Constructor (using xbool). Initializes xboolean::value from xb. Parameters: xb  the generating xbool

xboolean::xboolean (  bool  b  )  [inline]

Constructor (using bool). Initializes xboolean::value from b. Parameters: b  the generating bool

xboolean::xboolean (  const xboolean &  xb  )  [inline]

Copy constructor. Copies function xboolean::value from xb.value. Parameters: xb  the generating xboolean

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Member Function Documentation

virtual void xboolean::CalculateValue (  void   )  const [inline, virtual]

Must be overridden. It calculates a fresh function value and saves it in xboolean::value.

virtual void xboolean::CalculateValue (  void   )  [inline, virtual]

Must be overridden. It calculates a fresh function value and saves it in xboolean::value. Reimplemented in xpRuleGeneric.

virtual xbool xboolean::GetValue (  void   )  const [inline, virtual]

Calls xboolean::CalculateValue and returns the new value. Returns: xboolean::value, after recalculating it

virtual xbool xboolean::GetValue (  void   )  [inline, virtual]

Calls xboolean::CalculateValue and returns the new value. Returns: xboolean::value, after recalculating it

virtual wxString xboolean::GetValueString (  void   )  [inline, virtual]

Returns a one-character string, according to the result returned by xboolean::IsTrue, xboolean::IsFalse, xboolean::IsUnknown Returns: char, corresponding to the value Reimplemented in xpRuleGeneric.

bool xboolean::IsFalse (  void   )  [inline]

Calls xboolean::GetValue and return 'true' if the xboolean::value is False. Returns: true if the value is exactly False

bool xboolean::IsTrue (  void   )  [inline]

Calls xboolean::GetValue and return 'true' if the xboolean::value is True. Returns: true if the value is exactly True

bool xboolean::IsUnknown (  void   )  [inline]

Calls xboolean::GetValue and return 'true' if the xboolean::value is Unknown. Returns: true if the value is exactly Unknown

xboolean xboolean::operator! (  void   )  [inline]

! (negation) operator. It calls xboolean::GetValue and returns the negated value Returns: result of logical negation for the extended boolean Reimplemented in xpRuleGeneric.

xboolean xboolean::operator!= (  bool &  b  )  [inline]

Parameters: !=  logical non-identity operator calls xboolean::GetValue for this and return the result of their NOT EQUAL relation b  the operand Returns: result of non-identity check for the extended boolean and a boolean

xboolean xboolean::operator!= (  xboolean &  xb  )  [inline]

Parameters: !=  logical non-identity operator. It calls xboolean::GetValue for both this and xb and return the result of their NOT EQUAL relation xb  the operand Returns: result of non-identity check for the extended booleans

xboolean& xboolean::operator= (  bool &  b  )  [inline]

= (assign) operator. It assigns the value of b to this Parameters: b  : the assigning bool Returns: the extended boolean, set by a bool

xboolean& xboolean::operator= (  const xboolean &  xb  )  [inline]

Parameters: =  (assign) operator. It calls xboolean::CalculateValue and assigns the value to this xb  : the assigning xboolean Returns: the extended boolean, set by xboolean

xboolean xboolean::operator== (  bool &  b  )  [inline]

Parameters: ==  (logical identity) operator. It calls xboolean::GetValue for this and return the result of their EQUAL relation b  the operand Returns: result of identity check for an extended booleans and a boolean

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Friends And Related Function Documentation

xboolean operator && (  xboolean &  xbL, bool &  bR )  [friend]

Parameters: &&  logical AND operator. It calls xboolean::GetValue for xbL and returns the result of the AND relation with bR xbL  the first (left) operand bR  the second (right) operand Returns: result of AND for an extended boolean and a boolean

xboolean operator && (  bool &  bL, xboolean &  xbR )  [friend]

Parameters: &&  logical AND operator calls xboolean::GetValue for xbR and return the result of the AND relation with bL bL  the first (left) operand xbR  the second (right) operand Returns: result of AND for a boolean and an extended boolean

xboolean operator && (  xboolean &  xbL, xboolean &  xbR )  [friend]

Parameters: &&  (logical AND) operator. It calls xboolean::GetValue for both xbL and xbR and returns the result of their AND relation xbL  the first (left) operand xbR  the second (right) operand Returns: result of AND for the extended booleans

xboolean operator== (  xboolean &  xbL, xboolean &  xbR )  [friend]

Parameters: ==  logical identity operator. It calls xboolean::GetValue for both bL and xbR and returns the result of their EQUAL relation xbL  the first (left) operand xbR  the second (right) operand Returns: result of identity check for the extended booleans

xboolean operator|| (  xboolean &  xbL, bool &  bR )  [friend]

Parameters: ||  logical OR operator. It calls xboolean::GetValue for xbL and returns the result of the OR relation with bR xbL  the first (left) operand bR  the second (right) operand Returns: result of OR for the extended boolean and a boolean

xboolean operator|| (  bool &  bL, xboolean &  xbR )  [friend]

Parameters: ||  logical OR operator. It calls xboolean::GetValue for xbR and return the result of the OR relation with bL bL  the first (left) operand xbR  the second (right) operand Returns: result of OR for a boolean and an extended boolean

xboolean operator|| (  xboolean &  xbL, xboolean &  xbR )  [friend]

Parameters: ||  logical OR operator. It calls xboolean::GetValue for both xbL and xbR and return the result of their OR relation xbL  the first (left) operand xbR  the second (right) operand Returns: result of OR for the extended booleans

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Field Documentation

enum xboolean::xbool xboolean::value

Stores the actual value.

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

• XBOOL.H

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