QtxEvalExpr Class Reference

String expression evaluator. More...

#include <QtxEvalExpr.h>

Public Types
enum	Error {   OK , OperandsNotMatch , InvalidResult , InvalidOperation ,   OperationsNull , InvalidToken , CloseExpected , ExcessClose ,   BracketsNotMatch , StackUnderflow , ExcessData }
	Parsing error type. More...

Public Member Functions
	QtxEvalExpr (const QString &=QString())
	Constructor. More...
	QtxEvalExpr (const bool, const QString &=QString())
	Constructor. More...
	~QtxEvalExpr ()
	Destructor. More...
QVariant	calculate (const QString &=QString())
	Evaluate the expression. More...
QString	expression () const
	Get the expression. More...
void	setExpression (const QString &)
	Set the expression. More...
Error	error () const
	Get the code of latest parsing error. More...
QtxEvalParser *	parser () const
	Get the expression parser. More...
bool	autoDeleteOperationSets () const
	Get the 'auto-delete operations' flag value. More...
void	setAutoDeleteOperationSets (const bool)
	Set the 'auto-delete operations' flag value. More...
QList< QtxEvalSet * >	operationSets () const
	Get current set of operations. More...
QtxEvalSet *	operationSet (const QString &) const
	Get the operation by name. More...
void	removeOperationSet (QtxEvalSet *)
	Remove the operation. More...
void	insertOperationSet (QtxEvalSet *, const int=-1)
	Install the operation. More...

Private Member Functions
void	intialize (const bool, const QString &)
	Initialize the evaluator. More...

Private Attributes
QString	myExpr
QtxEvalParser *	myParser

Detailed Description

String expression evaluator.

Member Enumeration Documentation

Error

enum QtxEvalExpr::Error

Parsing error type.

Enumerator
OK	No errors found.
OperandsNotMatch	Types of arguments are invalid for this operation.
InvalidResult	Operation cannot find result (for example, division by zero)
InvalidOperation	Unknown operation.
OperationsNull	Internal operations pointer of parser is null.
InvalidToken	Invalid token (neither operation, nor parameter of value)
CloseExpected	Closing bracket is expected.
ExcessClose	Extra closing bracket is found.
BracketsNotMatch	Opening and closing brackets are of different type, e.g. [)
StackUnderflow	There are no arguments in the stack for the operation.
ExcessData	The parsing is finished, but there are more then one value in the stack.

Constructor & Destructor Documentation

QtxEvalExpr() [1/2]

QtxEvalExpr::QtxEvalExpr

(

const QString &

expr = QString()

)

Constructor.

The evaluator is initalized by standard operations. Use another constructor with parameter stdSets = false to avoid initialization of evaluator with standard operations.

Parameters

expr	expression to be evaluated

References intialize().

QtxEvalExpr() [2/2]

QtxEvalExpr::QtxEvalExpr	(	const bool	stdSets,
		const QString &	expr = QString()
	)

Constructor.

Parameters

stdSets	if true, the evaluator is initalized by standard operations
expr	expression to be evaluated

References intialize().

~QtxEvalExpr()

QtxEvalExpr::~QtxEvalExpr

(

)

Destructor.

References myParser.

Member Function Documentation

autoDeleteOperationSets()

bool QtxEvalExpr::autoDeleteOperationSets

(

)

const

Get the 'auto-delete operations' flag value.

Returns

true if all operations shoud be automatically deleted when the evaluator is destroyed

See also

setAutoDeleteOperationSets()

References QtxEvalParser::autoDeleteOperationSets(), and myParser.

calculate()

QVariant QtxEvalExpr::calculate

(

const QString &

expr = QString()

)

Evaluate the expression.

Parameters

expr	expression to be evaluated

Returns

result of the evaluation

References QtxEvalParser::calculate(), myParser, and setExpression().

error()

QtxEvalExpr::Error QtxEvalExpr::error

(

)

const

Get the code of latest parsing error.

Returns

the code of the last error

References QtxEvalParser::error(), and myParser.

expression()

QString QtxEvalExpr::expression

(

)

const

Get the expression.

Returns

expression string

References myExpr.

insertOperationSet()

void QtxEvalExpr::insertOperationSet	(	QtxEvalSet *	set,
		const int	idx = -1
	)

Install the operation.

Parameters

operation	to be added
idx	index in the list at which the operation shoud be inserted

See also

operationSets(), removeOperationSet(), operationSet()

References QtxEvalParser::insertOperationSet(), and myParser.

intialize()

void QtxEvalExpr::intialize ( const bool  stdSets, const QString &  expr  )

private

Initialize the evaluator.

Parameters

stdSets	if true, the evaluator is initalized by standard operations
expr	expression to be evaluated

References QtxEvalParser::insertOperationSet(), myParser, QtxEvalParser::setAutoDeleteOperationSets(), and setExpression().

operationSet()

QtxEvalSet * QtxEvalExpr::operationSet

(

const QString &

name

)

const

Get the operation by name.

Parameters

name	operation name

Returns

operation of 0 if not found

See also

operationSets(), insertOperationSet(), removeOperationSet()

References myParser, and QtxEvalParser::operationSet().

operationSets()

QList< QtxEvalSet * > QtxEvalExpr::operationSets

(

)

const

Get current set of operations.

Returns

operations set

See also

insertOperationSet(), removeOperationSet(), operationSet()

References myParser, and QtxEvalParser::operationSets().

parser()

QtxEvalParser * QtxEvalExpr::parser

(

)

const

Get the expression parser.

Returns

expression parser

References myParser.

removeOperationSet()

void QtxEvalExpr::removeOperationSet

(

QtxEvalSet *

set

)

Remove the operation.

Parameters

operation

to be removed

See also

operationSets(), insertOperationSet(), operationSet()

References myParser, and QtxEvalParser::removeOperationSet().

setAutoDeleteOperationSets()

void QtxEvalExpr::setAutoDeleteOperationSets

(

const bool

on

)

Set the 'auto-delete operations' flag value.

Parameters

on	if true, all operations shoud be automatically deleted when the evaluator is destroyed

See also

autoDeleteOperationSets()

References myParser, and QtxEvalParser::setAutoDeleteOperationSets().

setExpression()

void QtxEvalExpr::setExpression

(

const QString &

expr

)

Set the expression.

Parameters

expr	expression string

References expression(), myExpr, myParser, and QtxEvalParser::setExpression().

Member Data Documentation

myExpr

QString QtxEvalExpr::myExpr

private

myParser

QtxEvalParser* QtxEvalExpr::myParser

private

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

• src/Qtx/QtxEvalExpr.h
• src/Qtx/QtxEvalExpr.cxx