cDynamicExpression Class Reference

#include <cdynamicexpression.h>

Description

A stack-based expression evaluator class, for dynamically created expressions.

Inheritance diagram for cDynamicExpression:

Classes
class	Elem
	One element in a (reverse Polish) expression. More...
class	Functor
	Function object base class. We use function objects to handle NED parameter references, "index" and "sizeof" operators, and references to NED "for" loop variables. More...

Public Types
enum	OpType

Public Member Functions
Constructors, destructor, assignment.
	cDynamicExpression ()
	cDynamicExpression (const cDynamicExpression &other)
virtual	~cDynamicExpression ()
cDynamicExpression &	operator= (const cDynamicExpression &other)
Redefined cObject functions
virtual cDynamicExpression *	dup () const override
virtual std::string	str () const override
Setter and evaluator methods.
virtual void	setExpression (Elem e[], int size)
virtual cNedValue	evaluate (Context *context) const override
virtual bool	boolValue (Context *context) const override
virtual intpar_t	intValue (Context *context, const char *expectedUnit=nullptr) const override
virtual double	doubleValue (Context *context, const char *expectedUnit=nullptr) const override
virtual std::string	stringValue (Context *context) const override
virtual cXMLElement *	xmlValue (Context *context) const override
Public Member Functions inherited from cExpression
	cExpression ()
	cExpression (const cExpression &other)
virtual	~cExpression ()
cExpression &	operator= (const cExpression &other)
virtual void	parsimPack (cCommBuffer *buffer) const override
virtual void	parsimUnpack (cCommBuffer *buffer) override
virtual cNedValue	evaluate (cComponent *contextComponent=nullptr) const
virtual bool	boolValue (cComponent *contextComponent=nullptr) const
virtual intpar_t	intValue (cComponent *contextComponent=nullptr, const char *expectedUnit=nullptr) const
virtual double	doubleValue (cComponent *contextComponent=nullptr, const char *expectedUnit=nullptr) const
virtual std::string	stringValue (cComponent *contextComponent=nullptr) const
virtual cXMLElement *	xmlValue (cComponent *contextComponent=nullptr) const
Public Member Functions inherited from cObject
	cObject ()
	cObject (const cObject &other)
virtual	~cObject ()
virtual const char *	getClassName () const
virtual const char *	getName () const
bool	isName (const char *s) const
virtual const char *	getFullName () const
virtual std::string	getFullPath () const
const cObject *	getThisPtr () const
virtual _OPPDEPRECATED std::string	info () const
virtual _OPPDEPRECATED std::string	detailedInfo () const
virtual cObject *	getOwner () const
virtual bool	isOwnedObject () const
virtual void	forEachChild (cVisitor *v)
cObject *	findObject (const char *name, bool deep=true)
void	copyNotSupported () const

Miscellaneous utility functions.
virtual void	parse (const char *text) override
virtual int	compare (const cExpression *other) const override
virtual bool	isAConstant () const
virtual bool	containsConstSubexpressions () const override
virtual void	evaluateConstSubexpressions (Context *context) override
static double	convertUnit (double d, const char *unit, const char *targetUnit)

Additional Inherited Members
Protected Member Functions inherited from cObject
virtual void	take (cOwnedObject *obj)
virtual void	drop (cOwnedObject *obj)
void	dropAndDelete (cOwnedObject *obj)

Member Enumeration Documentation

OpType

enum OpType

Operations supported by this class:

• add, subtract, multiply, divide ("+" is also string concatenation)
• modulo, power of, negation (-1)
• equal, not equal, greater, greater or equal, less, less or equal
• inline if (the C/C++ ?: operator)
• logical and, or, xor, not
• bitwise and, or, xor, not (1's complement)
• left shift, right shift

Constructor & Destructor Documentation

cDynamicExpression() [1/2]

cDynamicExpression ( )

explicit

Constructor.

cDynamicExpression() [2/2]

cDynamicExpression ( const cDynamicExpression &  other )

inline

Copy constructor.

~cDynamicExpression()

virtual ~cDynamicExpression ( )

virtual

Destructor.

Member Function Documentation

operator=()

cDynamicExpression& operator=

(

const cDynamicExpression &

other

)

Assignment operator.

dup()

virtual cDynamicExpression* dup ( ) const

inlineoverridevirtual

Creates and returns an exact copy of this object.

Reimplemented from cExpression.

References cExpression::boolValue(), cExpression::doubleValue(), cExpression::evaluate(), cExpression::intValue(), cExpression::stringValue(), and cExpression::xmlValue().

str()

virtual std::string str ( ) const

overridevirtual

Converts the expression to string. See cObject for more details.

Reimplemented from cExpression.

setExpression()

virtual void setExpression ( Elem  e[], int  size  )

virtual

Sets the Reverse Polish expression to evaluate. The array must be a dynamically allocated one, and will be deleted by this object. No verification is performed on the expression at this time.

evaluate()

virtual cNedValue evaluate ( Context *  context ) const

overridevirtual

Evaluate the expression, and return the results as a cNedValue. Throws an error if the expression has some problem (i.e. stack overflow/underflow, "cannot cast", "function not found", etc.)

Implements cExpression.

boolValue()

virtual bool boolValue ( Context *  context ) const

overridevirtual

Evaluate the expression and convert the result to bool if possible; throw an error if conversion from that type is not supported.

Implements cExpression.

intValue()

virtual intpar_t intValue ( Context *  context, const char *  expectedUnit = nullptr  ) const

overridevirtual

Evaluate the expression and convert the result to intpar_t if possible; throw an error if conversion from that type is not supported, or the value of out of the range of intpar_t.

Implements cExpression.

doubleValue()

virtual double doubleValue ( Context *  context, const char *  expectedUnit = nullptr  ) const

overridevirtual

Evaluate the expression and convert the result to double if possible; throw an error if conversion from that type is not supported.

Implements cExpression.

stringValue()

virtual std::string stringValue ( Context *  context ) const

overridevirtual

Evaluate the expression and convert the result to string if possible; throw an error if conversion from that type is not supported.

Implements cExpression.

xmlValue()

virtual cXMLElement* xmlValue ( Context *  context ) const

overridevirtual

Evaluate the expression and convert the result to an XML tree if possible; throw an error if conversion from that type is not supported.

Implements cExpression.

parse()

virtual void parse ( const char *  text )

overridevirtual

Interprets the string as an expression, and stores it.

Implements cExpression.

compare()

virtual int compare ( const cExpression *  other ) const

overridevirtual

Compares two expressions.

Implements cExpression.

isAConstant()

virtual bool isAConstant ( ) const

virtual

Returns true if the expression is just a literal (or equivalent to one, like "2+2").

containsConstSubexpressions()

virtual bool containsConstSubexpressions ( ) const

overridevirtual

Returns true if this expression contains const subexpressions.

Implements cExpression.

evaluateConstSubexpressions()

virtual void evaluateConstSubexpressions ( Context *  context )

overridevirtual

Evaluates const subexpressions, and replaces them with their values. See cDynamicExpression::Elem::CONSTSUBEXPR.

Implements cExpression.

convertUnit()

static double convertUnit ( double  d, const char *  unit, const char *  targetUnit  )

static

Convert the given number into the target unit (e.g. milliwatt to watt). Throws an exception if conversion is not possible (unknown/unrelated units).

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

• cdynamicexpression.h