The base class for all value and parse types in Qore expression trees. More...

#include <AbstractQoreNode.h>

Inheritance diagram for AbstractQoreNode:

Collaboration diagram for AbstractQoreNode:

Public Member Methods
DLLEXPORT	AbstractQoreNode (const AbstractQoreNode &v)
	copy constructor

DLLEXPORT	AbstractQoreNode (qore_type_t t, bool n_value, bool n_needs_eval, bool n_there_can_be_only_one=false, bool n_custom_reference_handlers=false)
	constructor takes the type More...

virtual DLLEXPORT void	customDeref (ExceptionSink *xsink)

virtual DLLEXPORT void	customRef () const
	special processing when the object's reference count transitions from 0-1 More...

DLLEXPORT void	deref (ExceptionSink *xsink)
	decrements the reference count and calls derefImpl() if there_can_be_only_one is false, otherwise does nothing More...

virtual DLLEXPORT bool	derefImpl (ExceptionSink *xsink)
	decrements the reference count More...

DLLEXPORT QoreValue	eval (bool &needs_deref, ExceptionSink *xsink) const
	optionally evaluates the argument More...

DLLEXPORT QoreValue	eval (ExceptionSink *xsink) const
	evaluates the object and returns a value (or 0) More...

virtual DLLEXPORT QoreValue	evalImpl (bool &needs_deref, ExceptionSink *xsink) const =0
	optionally evaluates the argument More...

DLLEXPORT int64	getAsBigInt () const
	returns the 64-bit integer value of the object More...

virtual DLLLOCAL int64	getAsBigIntImpl () const
	default implementation, returns 0 More...

DLLEXPORT bool	getAsBool () const
	returns the boolean value of the object More...

virtual DLLLOCAL bool	getAsBoolImpl () const
	default implementation, returns false More...

DLLEXPORT double	getAsFloat () const
	returns the float value of the object More...

virtual DLLLOCAL double	getAsFloatImpl () const
	default implementation, returns 0.0 More...

DLLEXPORT int	getAsInt () const
	returns the integer value of the object More...

virtual DLLLOCAL int	getAsIntImpl () const
	default implementation, returns 0 More...

virtual DLLEXPORT QoreString *	getAsString (bool &del, int foff, ExceptionSink *xsink) const =0
	returns a QoreString giving the verbose string representation of the value (including all contained values for container types) More...

virtual DLLEXPORT int	getAsString (QoreString &str, int foff, ExceptionSink *xsink) const =0
	concatenate the verbose string representation of the value (including all contained values for container types) to an existing QoreString More...

virtual DLLEXPORT class DateTime *	getDateTimeRepresentation (bool &del) const
	returns the DateTime representation of this type (default implementation: returns ZeroDate, del = false) More...

virtual DLLEXPORT void	getDateTimeRepresentation (DateTime &dt) const
	assigns the date representation of a value to the DateTime reference passed, default implementation does nothing More...

virtual DLLEXPORT QoreString *	getStringRepresentation (bool &del) const
	returns the value of the type converted to a string, default implementation: returns the empty string More...

virtual DLLEXPORT void	getStringRepresentation (QoreString &str) const
	concatentates the value of the type to an existing QoreString reference, default implementation does nothing More...

DLLLOCAL qore_type_t	getType () const
	returns the data type More...

virtual DLLEXPORT const char *	getTypeName () const =0
	returns the type name as a c string More...

virtual DLLEXPORT bool	is_equal_hard (const AbstractQoreNode v, ExceptionSink xsink) const =0
	tests for equality ("deep compare" including all contained values for container types) without type conversions (hard compare) More...

virtual DLLEXPORT bool	is_equal_soft (const AbstractQoreNode v, ExceptionSink xsink) const =0
	tests for equality ("deep compare" including all contained values for container types) with possible type conversion (soft compare) More...

DLLLOCAL bool	is_value () const
	returns true if the node represents a value More...

DLLLOCAL bool	isReferenceCounted () const
	returns true if the object is reference-counted

DLLLOCAL bool	needs_eval () const
	returns true if the object needs evaluation to return a value, false if not More...

DLLLOCAL AbstractQoreNode &	operator= (const AbstractQoreNode &)
	this function is not implemented; it is here as a private function in order to prohibit it from being used

virtual DLLLOCAL int	parseInit (QoreValue &val, QoreParseContext &parse_context)
	for use by parse types to initialize them for execution during stage 1 parsing More...

virtual DLLEXPORT AbstractQoreNode *	realCopy () const =0
	returns a copy of the object; the caller owns the reference count More...

DLLEXPORT void	ref () const
	increments the reference count

DLLEXPORT AbstractQoreNode *	refSelf () const
	returns "this" with an incremented reference count More...

Public Member Methods inherited from QoreReferenceCounter
DLLEXPORT	QoreReferenceCounter ()
	creates the reference counter object

DLLEXPORT	QoreReferenceCounter (const QoreReferenceCounter &old)
	creates a new object with a reference count of 1 More...

DLLEXPORT	~QoreReferenceCounter ()
	destroys the reference counter object

DLLEXPORT bool	is_unique () const
	returns true if the reference count is 1 More...

DLLEXPORT int	reference_count () const
	gets the reference count More...

DLLEXPORT bool	ROdereference () const
	atomically decrements the reference count More...

DLLEXPORT void	ROreference () const
	atomically increments the reference count

Private Member Methods
virtual DLLEXPORT	~AbstractQoreNode ()
	default destructor does nothing More...

Private Attributes
bool	custom_reference_handlers: 1
	set to one for objects that need custom reference handlers

bool	needs_eval_flag: 1
	if this is true then the type can be evaluated

bool	there_can_be_only_one: 1
	if this is set to true, then reference counting is turned off for objects of this class

qore_type_t	type: 11
	the type of the object More...

bool	value: 1
	this is true for values, if false then either the type needs evaluation to produce a value or is a parse expression

Detailed Description

The base class for all value and parse types in Qore expression trees.

Defines the interface for all value and parse types in Qore expression trees. Default implementations are given for most virtual functions.

Constructor & Destructor Documentation

◆ AbstractQoreNode()

DLLEXPORT AbstractQoreNode::AbstractQoreNode	(	qore_type_t	t,
		bool	n_value,
		bool	n_needs_eval,
		bool	n_there_can_be_only_one = `false`,
		bool	n_custom_reference_handlers = `false`
	)

constructor takes the type

The type code for the class is passed as the argument to the constructor

Parameters

t	the Qore type code identifying this class in the Qore type system
n_value	determines if this is a value type or not
n_needs_eval	determines if the type needs evaluation when AbstractQoreNode::eval() is called
n_there_can_be_only_one	whereas this type is normally reference counted, if this is set to true, then referencing counting is turned off for this type. This can only be turned on when the type represents a single value.
n_custom_reference_handlers	if true then the class implements its own reference handlers

◆ ~AbstractQoreNode()

virtual DLLEXPORT AbstractQoreNode::~AbstractQoreNode ( )

privatevirtual

default destructor does nothing

The destructor is protected because it should not be called directly, which also means that these objects cannot normally be created on the stack. They are referenced counted, and the deref() function should be used to decrement the reference count rather than using the delete operator. Because the QoreObject class at least could throw a Qore Exception when it is deleted, AbstractQoreNode::deref() takes an ExceptionSink pointer argument by default as well.

Member Function Documentation

◆ customDeref()

virtual DLLEXPORT void AbstractQoreNode::customDeref ( ExceptionSink * xsink )

virtual

only called when custom_reference_handlers = true. The default implementation does nothing (calls assert(false) in debug mode)

Reimplemented in QoreObject.

◆ customRef()

virtual DLLEXPORT void AbstractQoreNode::customRef ( ) const

virtual

special processing when the object's reference count transitions from 0-1

only called when custom_reference_handlers = true. The default implementation does nothing (calls assert(false) in debug mode)

Reimplemented in QoreObject.

◆ deref()

DLLEXPORT void AbstractQoreNode::deref ( ExceptionSink * xsink )

decrements the reference count and calls derefImpl() if there_can_be_only_one is false, otherwise does nothing

if there_can_be_only_one is false, calls derefImpl() and deletes the object when the reference count = 0. The ExceptionSink argument is needed for those types that could throw an exception when they are deleted (ex: QoreObject)

Parameters

xsink if an error occurs, the Qore-language exception information will be added here

Referenced by discard().

◆ derefImpl()

virtual DLLEXPORT bool AbstractQoreNode::derefImpl ( ExceptionSink * xsink )

virtual

decrements the reference count

deletes the object when the reference count = 0. The ExceptionSink argument is needed for those types that could throw an exception when they are deleted (ex: QoreObject)

Parameters

xsink if an error occurs, the Qore-language exception information will be added here

Returns: true if the object can be deleted, false if not (externally-managed)

Reimplemented in FunctionCallReferenceNode, QoreHashNode, QoreListNode, QoreObject, and ReferenceNode.

◆ eval() [1/2]

DLLEXPORT QoreValue AbstractQoreNode::eval	(	bool &	needs_deref,
		ExceptionSink *	xsink
	)		const

optionally evaluates the argument

return value requires a dereference if needs_deref is true if needs_eval() is true, needs_deref = true, returns evalImpl() otherwise needs_deref = false returns "this"

Parameters

needs_deref	this is an output parameter, if needs_deref is true then the value returned must be dereferenced
xsink	if an error occurs, the Qore-language exception information will be added here

Note: do not use this function directly, use the ValueEvalRefHolder class instead

See also: ValueEvalRefHolder

◆ eval() [2/2]

DLLEXPORT QoreValue AbstractQoreNode::eval ( ExceptionSink * xsink ) const

evaluates the object and returns a value (or 0)

return value requires a deref(xsink) (if not 0). If needs_eval() returns false, then this function just returns refSelf(). Otherwise evalImpl() is returned.

ValueHolder value(n->eval(xsink));
if (!*value) // note that if a qore-language exception occured, then value = 0
    return 0;
...
return value.release();

Parameters

xsink if an error occurs, the Qore-language exception information will be added here

Returns: the result of the evaluation, if the return value contains a referenced value, it must be dereferenced manually

See also

◆ evalImpl()

virtual DLLEXPORT QoreValue AbstractQoreNode::evalImpl	(	bool &	needs_deref,
		ExceptionSink *	xsink
	)		const

pure virtual

optionally evaluates the argument

return value requires a dereference if needs_deref is true if needs_eval() is true, needs_deref = true, returns evalImpl() otherwise needs_deref = false returns "this"

Parameters

needs_deref	this is an output parameter, if needs_deref is true then the value returned must be dereferenced
xsink	if an error occurs, the Qore-language exception information will be added here

Note: do not use this function directly, use the ValueEvalRefHolder class instead

See also: eval(bool&, ExceptionSink*)

Implemented in SimpleValueQoreNode, AbstractCallReferenceNode, ResolvedCallReferenceNode, LocalStaticMethodCallReferenceNode, LocalMethodCallReferenceNode, LocalFunctionCallReferenceNode, SetSelfFunctionCallNode, QoreHashNode, QoreListNode, QoreNothingNode, QoreNothingNode, QoreNullNode, QoreNullNode, QoreObject, and ReferenceNode.

◆ getAsBigInt()

DLLEXPORT int64 AbstractQoreNode::getAsBigInt ( ) const

returns the 64-bit integer value of the object

calls getAsBitIntImpl() if necessary to return the integer value of the object

◆ getAsBigIntImpl()

virtual DLLLOCAL int64 AbstractQoreNode::getAsBigIntImpl ( ) const

inlinevirtual

default implementation, returns 0

This function is called by the normal class function "getAsBigInt()"

Returns: the value of the object interpreted as a 64-bit integer

◆ getAsBool()

DLLEXPORT bool AbstractQoreNode::getAsBool ( ) const

returns the boolean value of the object

calls getAsBoolImpl() if necessary to return the boolean value of the object

◆ getAsBoolImpl()

virtual DLLLOCAL bool AbstractQoreNode::getAsBoolImpl ( ) const

inlinevirtual

default implementation, returns false

This function is called by the normal class function "getAsBool()"

Returns: the value of the object interpreted as a boolean

Reimplemented in BinaryNode, AbstractCallReferenceNode, QoreHashNode, QoreListNode, and QoreObject.

◆ getAsFloat()

DLLEXPORT double AbstractQoreNode::getAsFloat ( ) const

returns the float value of the object

calls getAsFloatImpl() if necessary to return the floating-point value of the object

◆ getAsFloatImpl()

virtual DLLLOCAL double AbstractQoreNode::getAsFloatImpl ( ) const

inlinevirtual

default implementation, returns 0.0

This function is called by the normal class function "getAsFloat()"

Returns: the value of the object interpreted as a floating-point number

◆ getAsInt()

DLLEXPORT int AbstractQoreNode::getAsInt ( ) const

returns the integer value of the object

calls getAsIntImpl() if necessary to return the integer value of the object

◆ getAsIntImpl()

virtual DLLLOCAL int AbstractQoreNode::getAsIntImpl ( ) const

inlinevirtual

default implementation, returns 0

This function is called by the normal class function "getAsInt()"

Returns: the value of the object interpreted as an integer

◆ getAsString() [1/2]

virtual DLLEXPORT QoreString * AbstractQoreNode::getAsString	(	bool &	del,
		int	foff,
		ExceptionSink *	xsink
	)		const

pure virtual

returns a QoreString giving the verbose string representation of the value (including all contained values for container types)

Used for n and N printf formatting. Do not call this function directly; use the QoreNodeAsStringHelper class (defined in QoreStringNode.h) instead

Parameters

del	if this is true when the function returns, then the returned QoreString pointer should be deleted, if false, then it must not be
foff	for multi-line formatting offset, -1 = no line breaks
xsink	if an error occurs, the Qore-language exception information will be added here

See also: QoreNodeAsStringHelper

Implemented in BinaryNode, QoreNothingNode, QoreNullNode, QoreNumberNode, AbstractCallReferenceNode, DateTimeNode, QoreHashNode, QoreListNode, QoreObject, ReferenceNode, and QoreStringNode.

◆ getAsString() [2/2]

virtual DLLEXPORT int AbstractQoreNode::getAsString	(	QoreString &	str,
		int	foff,
		ExceptionSink *	xsink
	)		const

pure virtual

concatenate the verbose string representation of the value (including all contained values for container types) to an existing QoreString

used for n and N printf formatting

Parameters

str	the string representation of the type will be concatenated to this QoreString reference
foff	for multi-line formatting offset, -1 = no line breaks
xsink	if an error occurs, the Qore-language exception information will be added here

Returns: -1 for exception raised, 0 = OK

Implemented in BinaryNode, QoreNothingNode, QoreNullNode, QoreNumberNode, AbstractCallReferenceNode, DateTimeNode, QoreHashNode, QoreListNode, QoreObject, ReferenceNode, and QoreStringNode.

◆ getDateTimeRepresentation() [1/2]

virtual DLLEXPORT class DateTime * AbstractQoreNode::getDateTimeRepresentation ( bool & del ) const

virtual

returns the DateTime representation of this type (default implementation: returns ZeroDate, del = false)

NOTE: Use the DateTimeValueHelper class instead of using this function directly

Parameters

del	output parameter: if del is true, then the returned DateTime pointer belongs to the caller (and must be deleted manually), if false, then it must not be

See also: DateTimeValueHelper

Reimplemented in DateTimeNode, QoreNumberNode, and QoreStringNode.

Referenced by DateTimeNodeValueHelper::DateTimeNodeValueHelper().

◆ getDateTimeRepresentation() [2/2]

virtual DLLEXPORT void AbstractQoreNode::getDateTimeRepresentation ( DateTime & dt ) const

virtual

assigns the date representation of a value to the DateTime reference passed, default implementation does nothing

Parameters

dt	the DateTime reference to be assigned

Reimplemented in DateTimeNode, QoreNumberNode, and QoreStringNode.

◆ getStringRepresentation() [1/2]

virtual DLLEXPORT QoreString * AbstractQoreNode::getStringRepresentation ( bool & del ) const

virtual

returns the value of the type converted to a string, default implementation: returns the empty string

NOTE: do not use this function directly, use QoreStringValueHelper instead

Parameters

del	output parameter: if del is true, then the resulting QoreString pointer belongs to the caller (and must be deleted manually), if false it must not be

Returns: a QoreString pointer, use the del output parameter to determine ownership of the pointer

See also: QoreStringValueHelper

Reimplemented in DateTimeNode, QoreNumberNode, and QoreStringNode.

◆ getStringRepresentation() [2/2]

virtual DLLEXPORT void AbstractQoreNode::getStringRepresentation ( QoreString & str ) const

virtual

concatentates the value of the type to an existing QoreString reference, default implementation does nothing

Parameters

str	a reference to a QoreString where the value of the type will be concatenated

Reimplemented in DateTimeNode, QoreNumberNode, and QoreStringNode.

◆ getType()

DLLLOCAL qore_type_t AbstractQoreNode::getType ( ) const

inline

returns the data type

Returns: the data type of the object

References type.

Referenced by DateTimeNodeValueHelper::DateTimeNodeValueHelper(), is_nothing(), and is_null().

◆ getTypeName()

virtual DLLEXPORT const char * AbstractQoreNode::getTypeName ( ) const

pure virtual

returns the type name as a c string

Returns: the type name as a c string

Implemented in BinaryNode, AbstractCallReferenceNode, DateTimeNode, QoreHashNode, QoreListNode, QoreNothingNode, QoreNullNode, QoreNumberNode, QoreObject, QoreStringNode, and ReferenceNode.

◆ is_equal_hard()

virtual DLLEXPORT bool AbstractQoreNode::is_equal_hard	(	const AbstractQoreNode *	v,
		ExceptionSink *	xsink
	)		const

pure virtual

tests for equality ("deep compare" including all contained values for container types) without type conversions (hard compare)

Parameters

v	the value to compare
xsink	if an error occurs, the Qore-language exception information will be added here

Returns: true if the objects are equal, false if not

Implemented in BinaryNode, ResolvedCallReferenceNode, DateTimeNode, LocalStaticMethodCallReferenceNode, LocalMethodCallReferenceNode, LocalFunctionCallReferenceNode, RunTimeObjectMethodReferenceNode, RunTimeResolvedMethodReferenceNode, QoreHashNode, QoreListNode, QoreNothingNode, QoreNullNode, QoreNumberNode, QoreObject, QoreStringNode, and ReferenceNode.

◆ is_equal_soft()

virtual DLLEXPORT bool AbstractQoreNode::is_equal_soft	(	const AbstractQoreNode *	v,
		ExceptionSink *	xsink
	)		const

pure virtual

tests for equality ("deep compare" including all contained values for container types) with possible type conversion (soft compare)

Parameters

v	the value to compare
xsink	if an error occurs, the Qore-language exception information will be added here

Returns: true if the objects are equal, false if not

Implemented in BinaryNode, ResolvedCallReferenceNode, DateTimeNode, LocalStaticMethodCallReferenceNode, LocalMethodCallReferenceNode, LocalFunctionCallReferenceNode, RunTimeObjectMethodReferenceNode, RunTimeResolvedMethodReferenceNode, QoreHashNode, QoreListNode, QoreNothingNode, QoreNullNode, QoreNumberNode, QoreObject, QoreStringNode, and ReferenceNode.

◆ is_value()

DLLLOCAL bool AbstractQoreNode::is_value ( ) const

inline

returns true if the node represents a value

Returns: true if the object is a value, false if not

References value.

◆ needs_eval()

DLLLOCAL bool AbstractQoreNode::needs_eval ( ) const

inline

returns true if the object needs evaluation to return a value, false if not

default implementation returns false

Returns: true if the type supports evaluation of this object, false if not

References needs_eval_flag.

◆ parseInit()

virtual DLLLOCAL int AbstractQoreNode::parseInit	(	QoreValue &	val,
		QoreParseContext &	parse_context
	)

virtual

for use by parse types to initialize them for execution during stage 1 parsing

Not exported in the library; this method's API/ABI subject to change at any time.

This function should only be overridden by types that can appear in the parse tree (i.e. are recognized by the parser)

Parameters

val	the containing QoreValue
parse_context	the parse context

Returns: -1 if an error occured, 0 if OK

Reimplemented in BinaryNode, ResolvedCallReferenceNode, DateTimeNode, UnresolvedProgramCallReferenceNode, UnresolvedStaticMethodCallReferenceNode, QoreHashNode, QoreListNode, QoreNothingNode, QoreNullNode, QoreNumberNode, and QoreStringNode.

◆ realCopy()

virtual DLLEXPORT AbstractQoreNode * AbstractQoreNode::realCopy ( ) const

pure virtual

returns a copy of the object; the caller owns the reference count

Returns: a copy of the object; the caller owns the reference count

Implemented in UniqueValueQoreNode, BinaryNode, ResolvedCallReferenceNode, DateTimeNode, QoreHashNode, QoreListNode, QoreNumberNode, QoreObject, QoreStringNode, and ReferenceNode.

◆ refSelf()

DLLEXPORT AbstractQoreNode * AbstractQoreNode::refSelf ( ) const

returns "this" with an incremented reference count

Returns: "this" with an incremented reference count

Member Data Documentation

◆ type

qore_type_t AbstractQoreNode::type

private

the type of the object

instead of using a virtual method to return a default type code for each implemented type, it's stored as an attribute of the base class. This makes it possible to avoid making virtual function calls as a performance optimization in many cases, also it allows very fast type determination without making either a virtual function call or using dynamic_cast<> at the expense of more memory usage

Referenced by getType().

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

/tmp/qore/include/qore/AbstractQoreNode.h

Public Member Methods

Private Member Methods

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ AbstractQoreNode()

◆ ~AbstractQoreNode()

Member Function Documentation

◆ customDeref()

◆ customRef()

◆ deref()

◆ derefImpl()

◆ eval() [1/2]

◆ eval() [2/2]

◆ evalImpl()

◆ getAsBigInt()

◆ getAsBigIntImpl()

◆ getAsBool()

◆ getAsBoolImpl()

◆ getAsFloat()

◆ getAsFloatImpl()

◆ getAsInt()

◆ getAsIntImpl()

◆ getAsString() [1/2]

◆ getAsString() [2/2]

◆ getDateTimeRepresentation() [1/2]

◆ getDateTimeRepresentation() [2/2]

◆ getStringRepresentation() [1/2]

◆ getStringRepresentation() [2/2]

◆ getType()

◆ getTypeName()

◆ is_equal_hard()

◆ is_equal_soft()

◆ is_value()

◆ needs_eval()

◆ parseInit()

◆ realCopy()

◆ refSelf()

Member Data Documentation

◆ type