A ValueObject that contains a root variable that may or may not have children. More...

#include <ValueObjectVariable.h>

Inheritance diagram for lldb_private::ValueObjectVariable:

Public Member Functions
	~ValueObjectVariable () override
llvm::Expected< uint64_t >	GetByteSize () override
ConstString	GetTypeName () override
ConstString	GetQualifiedTypeName () override
ConstString	GetDisplayTypeName () override
llvm::Expected< uint32_t >	CalculateNumChildren (uint32_t max) override
	Should only be called by ValueObject::GetNumChildren().
lldb::ValueType	GetValueType () const override
bool	IsInScope () override
lldb::ModuleSP	GetModule () override
	Return the module associated with this value object in case the value is from an executable file and might have its data in sections of the file.
SymbolContextScope *	GetSymbolContextScope () override
bool	GetDeclaration (Declaration &decl) override
const char *	GetLocationAsCString () override
bool	SetValueFromCString (const char *value_str, Status &error) override
bool	SetData (DataExtractor &data, Status &error) override
lldb::VariableSP	GetVariable () override
Public Member Functions inherited from lldb_private::ValueObject
virtual	~ValueObject ()
const EvaluationPoint &	GetUpdatePoint () const
EvaluationPoint &	GetUpdatePoint ()
const ExecutionContextRef &	GetExecutionContextRef () const
lldb::TargetSP	GetTargetSP () const
lldb::ProcessSP	GetProcessSP () const
lldb::ThreadSP	GetThreadSP () const
lldb::StackFrameSP	GetFrameSP () const
void	SetNeedsUpdate ()
CompilerType	GetCompilerType ()
virtual TypeImpl	GetTypeImpl ()
virtual bool	CanProvideValue ()
lldb::LanguageType	GetObjectRuntimeLanguage ()
uint32_t	GetTypeInfo (CompilerType *pointee_or_element_compiler_type=nullptr)
bool	IsPointerType ()
bool	IsArrayType ()
bool	IsScalarType ()
bool	IsPointerOrReferenceType ()
bool	IsPossibleDynamicType ()
bool	IsNilReference ()
bool	IsUninitializedReference ()
virtual bool	IsBaseClass ()
virtual bool	IsDereferenceOfParent ()
bool	IsIntegerType (bool &is_signed)
virtual void	GetExpressionPath (Stream &s, GetExpressionPathFormat=eGetExpressionPathFormatDereferencePointers)
lldb::ValueObjectSP	GetValueForExpressionPath (llvm::StringRef expression, ExpressionPathScanEndReason reason_to_stop=nullptr, ExpressionPathEndResultType final_value_type=nullptr, const GetValueForExpressionPathOptions &options=GetValueForExpressionPathOptions::DefaultOptions(), ExpressionPathAftermath *final_task_on_target=nullptr)
virtual lldb::offset_t	GetByteOffset ()
virtual uint32_t	GetBitfieldBitSize ()
virtual uint32_t	GetBitfieldBitOffset ()
bool	IsBitfield ()
virtual const char *	GetValueAsCString ()
virtual bool	GetValueAsCString (const lldb_private::TypeFormatImpl &format, std::string &destination)
bool	GetValueAsCString (lldb::Format format, std::string &destination)
virtual uint64_t	GetValueAsUnsigned (uint64_t fail_value, bool *success=nullptr)
virtual int64_t	GetValueAsSigned (int64_t fail_value, bool *success=nullptr)
llvm::Expected< llvm::APSInt >	GetValueAsAPSInt ()
	If the current ValueObject is of an appropriate type, convert the value to an APSInt and return that.
llvm::Expected< llvm::APFloat >	GetValueAsAPFloat ()
	If the current ValueObject is of an appropriate type, convert the value to an APFloat and return that.
llvm::Expected< bool >	GetValueAsBool ()
	If the current ValueObject is of an appropriate type, convert the value to a boolean and return that.
void	SetValueFromInteger (const llvm::APInt &value, Status &error, bool can_update_var=true)
	Update an existing integer ValueObject with a new integer value.
void	SetValueFromInteger (lldb::ValueObjectSP new_val_sp, Status &error, bool can_update_var=true)
	Update an existing integer ValueObject with an integer value created frome 'new_val_sp'.
ValueObject *	GetRoot ()
ValueObject *	FollowParentChain (std::function< bool(ValueObject *)>)
	Given a ValueObject, loop over itself and its parent, and its parent's parent, .
const Status &	GetError ()
ConstString	GetName () const
lldb::user_id_t	GetID () const
	Returns a unique id for this ValueObject.
virtual lldb::ValueObjectSP	GetChildAtIndex (uint32_t idx, bool can_create=true)
lldb::ValueObjectSP	GetChildAtNamePath (llvm::ArrayRef< llvm::StringRef > names)
virtual lldb::ValueObjectSP	GetChildMemberWithName (llvm::StringRef name, bool can_create=true)
virtual llvm::Expected< size_t >	GetIndexOfChildWithName (llvm::StringRef name)
llvm::Expected< uint32_t >	GetNumChildren (uint32_t max=UINT32_MAX)
uint32_t	GetNumChildrenIgnoringErrors (uint32_t max=UINT32_MAX)
	Like `GetNumChildren` but returns 0 on error.
bool	HasChildren ()
const Value &	GetValue () const
Value &	GetValue ()
virtual bool	ResolveValue (Scalar &scalar)
virtual bool	IsLogicalTrue (Status &error)
const char *	GetSummaryAsCString (lldb::LanguageType lang=lldb::eLanguageTypeUnknown)
bool	GetSummaryAsCString (TypeSummaryImpl *summary_ptr, std::string &destination, lldb::LanguageType lang=lldb::eLanguageTypeUnknown)
bool	GetSummaryAsCString (std::string &destination, const TypeSummaryOptions &options)
bool	GetSummaryAsCString (TypeSummaryImpl *summary_ptr, std::string &destination, const TypeSummaryOptions &options)
llvm::Expected< std::string >	GetObjectDescription ()
bool	HasSpecialPrintableRepresentation (ValueObjectRepresentationStyle val_obj_display, lldb::Format custom_format)
bool	DumpPrintableRepresentation (Stream &s, ValueObjectRepresentationStyle val_obj_display=eValueObjectRepresentationStyleSummary, lldb::Format custom_format=lldb::eFormatInvalid, PrintableRepresentationSpecialCases special=PrintableRepresentationSpecialCases::eAllow, bool do_dump_error=true)
bool	GetValueIsValid () const
bool	GetValueDidChange ()
bool	UpdateValueIfNeeded (bool update_format=true)
bool	UpdateFormatsIfNeeded ()
lldb::ValueObjectSP	GetSP ()
void	SetName (ConstString name)
	Change the name of the current ValueObject.
virtual AddrAndType	GetAddressOf (bool scalar_is_load_address=true)
std::optional< lldb::addr_t >	GetStrippedPointerValue (lldb::addr_t address)
	Remove ptrauth bits from address if the type has a ptrauth qualifier.
AddrAndType	GetPointerValue ()
lldb::ValueObjectSP	GetSyntheticChild (ConstString key) const
lldb::ValueObjectSP	GetSyntheticArrayMember (size_t index, bool can_create)
lldb::ValueObjectSP	GetSyntheticBitFieldChild (uint32_t from, uint32_t to, bool can_create)
lldb::ValueObjectSP	GetSyntheticExpressionPathChild (const char *expression, bool can_create)
virtual lldb::ValueObjectSP	GetSyntheticChildAtOffset (uint32_t offset, const CompilerType &type, bool can_create, ConstString name_const_str=ConstString())
virtual lldb::ValueObjectSP	GetSyntheticBase (uint32_t offset, const CompilerType &type, bool can_create, ConstString name_const_str=ConstString())
virtual lldb::ValueObjectSP	GetDynamicValue (lldb::DynamicValueType valueType)
lldb::DynamicValueType	GetDynamicValueType ()
virtual lldb::ValueObjectSP	GetStaticValue ()
virtual lldb::ValueObjectSP	GetNonSyntheticValue ()
lldb::ValueObjectSP	GetSyntheticValue ()
virtual bool	HasSyntheticValue ()
virtual bool	IsSynthetic ()
lldb::ValueObjectSP	GetQualifiedRepresentationIfAvailable (lldb::DynamicValueType dynValue, bool synthValue)
virtual lldb::ValueObjectSP	CreateConstantValue (ConstString name)
virtual lldb::ValueObjectSP	Dereference (Status &error)
virtual lldb::ValueObjectSP	Clone (ConstString new_name)
	Creates a copy of the ValueObject with a new name and setting the current ValueObject as its parent.
virtual lldb::ValueObjectSP	AddressOf (Status &error)
virtual lldb::addr_t	GetLiveAddress ()
virtual void	SetLiveAddress (lldb::addr_t addr=LLDB_INVALID_ADDRESS, AddressType address_type=eAddressTypeLoad)
lldb::ValueObjectSP	Cast (const CompilerType &compiler_type)
virtual lldb::ValueObjectSP	DoCast (const CompilerType &compiler_type)
virtual lldb::ValueObjectSP	CastPointerType (const char *name, CompilerType &ast_type)
virtual lldb::ValueObjectSP	CastPointerType (const char *name, lldb::TypeSP &type_sp)
lldb::addr_t	GetLoadAddress ()
	Return the target load address associated with this value object.
llvm::Expected< lldb::ValueObjectSP >	CastDerivedToBaseType (CompilerType type, const llvm::ArrayRef< uint32_t > &base_type_indices)
	Take a ValueObject whose type is an inherited class, and cast it to 'type', which should be one of its base classes.
llvm::Expected< lldb::ValueObjectSP >	CastBaseToDerivedType (CompilerType type, uint64_t offset)
	Take a ValueObject whose type is a base class, and cast it to 'type', which should be one of its derived classes.
lldb::ValueObjectSP	CastToBasicType (CompilerType type)
lldb::ValueObjectSP	CastToEnumType (CompilerType type)
lldb::ValueObjectSP	GetVTable ()
	If this object represents a C++ class with a vtable, return an object that represents the virtual function table.
void	ValueUpdated ()
virtual bool	IsDynamic ()
virtual bool	DoesProvideSyntheticValue ()
virtual bool	IsSyntheticChildrenGenerated ()
virtual void	SetSyntheticChildrenGenerated (bool b)
llvm::Error	Dump (Stream &s)
llvm::Error	Dump (Stream &s, const DumpValueObjectOptions &options)
lldb::ValueObjectSP	CreateChildValueObjectFromExpression (llvm::StringRef name, llvm::StringRef expression, const ExecutionContext &exe_ctx, const EvaluateExpressionOptions &options)
	These are the appropriate routines to make a ValueObject that get managed by this ValueObject (and all the other members of its Cluster).
lldb::ValueObjectSP	CreateChildValueObjectFromAddress (llvm::StringRef name, uint64_t address, const ExecutionContext &exe_ctx, CompilerType type, bool do_deref=true)
	Given an address either create a value object containing the value at that address, or create a value object containing the address itself (pointer value), depending on whether the parameter 'do_deref' is true or false.
lldb::ValueObjectSP	CreateChildValueObjectFromData (llvm::StringRef name, const DataExtractor &data, const ExecutionContext &exe_ctx, CompilerType type)
lldb::ValueObjectSP	CreateChildValueObjectFromAPInt (const ExecutionContext &exe_ctx, const llvm::APInt &v, CompilerType type, llvm::StringRef name)
	Create a value object containing the given APInt value.
lldb::ValueObjectSP	CreateChildValueObjectFromAPFloat (const ExecutionContext &exe_ctx, const llvm::APFloat &v, CompilerType type, llvm::StringRef name)
	Create a value object containing the given APFloat value.
lldb::ValueObjectSP	CreateChildValueObjectFromScalar (const ExecutionContext &exe_ctx, Scalar &s, CompilerType type, llvm::StringRef name)
	Create a value object containing the given Scalar value.
lldb::ValueObjectSP	CreateChildValueObjectFromBool (const ExecutionContext &exe_ctx, lldb::TypeSystemSP typesystem, bool value, llvm::StringRef name)
	Create a value object containing the given boolean value.
lldb::ValueObjectSP	CreateChildValueObjectFromNullptr (const ExecutionContext &exe_ctx, CompilerType type, llvm::StringRef name)
	Create a nullptr value object with the specified type (must be a nullptr type).
lldb::ValueObjectSP	Persist ()
bool	IsCStringContainer (bool check_pointer=false)
	Returns true if this is a char* or a char[] if it is a char* and check_pointer is true, it also checks that the pointer is valid.
std::pair< size_t, bool >	ReadPointedString (lldb::WritableDataBufferSP &buffer_sp, Status &error, bool honor_array)
virtual size_t	GetPointeeData (DataExtractor &data, uint32_t item_idx=0, uint32_t item_count=1)
virtual uint64_t	GetData (DataExtractor &data, Status &error)
virtual bool	GetIsConstant () const
bool	NeedsUpdating ()
void	SetIsConstant ()
lldb::Format	GetFormat () const
virtual void	SetFormat (lldb::Format format)
virtual lldb::LanguageType	GetPreferredDisplayLanguage ()
void	SetPreferredDisplayLanguage (lldb::LanguageType lt)
lldb::TypeSummaryImplSP	GetSummaryFormat ()
void	SetSummaryFormat (lldb::TypeSummaryImplSP format)
void	SetDerefValobj (ValueObject *deref)
ValueObject *	GetDerefValobj ()
void	SetValueFormat (lldb::TypeFormatImplSP format)
lldb::TypeFormatImplSP	GetValueFormat ()
void	SetSyntheticChildren (const lldb::SyntheticChildrenSP &synth_sp)
lldb::SyntheticChildrenSP	GetSyntheticChildren ()
virtual ValueObject *	GetParent ()
virtual const ValueObject *	GetParent () const
ValueObject *	GetNonBaseClassParent ()
void	SetAddressTypeOfChildren (AddressType at)
AddressType	GetAddressTypeOfChildren ()
void	SetHasCompleteType ()
virtual bool	MightHaveChildren ()
	Find out if a ValueObject might have children.
virtual bool	IsRuntimeSupportValue ()
virtual uint64_t	GetLanguageFlags ()
virtual void	SetLanguageFlags (uint64_t flags)
llvm::ArrayRef< uint8_t >	GetLocalBuffer () const
	Returns the local buffer that this ValueObject points to if it's available.
lldb::ValueObjectSP	CheckValueObjectOwnership (ValueObject *child)

Static Public Member Functions
static lldb::ValueObjectSP	Create (ExecutionContextScope *exe_scope, const lldb::VariableSP &var_sp)
Static Public Member Functions inherited from lldb_private::ValueObject
static lldb::ValueObjectSP	CreateValueObjectFromExpression (llvm::StringRef name, llvm::StringRef expression, const ExecutionContext &exe_ctx, ValueObject *parent=nullptr)
	The following static routines create "Root" ValueObjects if parent is null.
static lldb::ValueObjectSP	CreateValueObjectFromExpression (llvm::StringRef name, llvm::StringRef expression, const ExecutionContext &exe_ctx, const EvaluateExpressionOptions &options, ValueObject *parent=nullptr)
static lldb::ValueObjectSP	CreateValueObjectFromAddress (llvm::StringRef name, uint64_t address, const ExecutionContext &exe_ctx, CompilerType type, bool do_deref=true, ValueObject *parent=nullptr)
	Given an address either create a value object containing the value at that address, or create a value object containing the address itself (pointer value), depending on whether the parameter 'do_deref' is true or false.
static lldb::ValueObjectSP	CreateValueObjectFromData (llvm::StringRef name, const DataExtractor &data, const ExecutionContext &exe_ctx, CompilerType type, ValueObject *parent=nullptr)
static lldb::ValueObjectSP	CreateValueObjectFromAPInt (const ExecutionContext &exe_ctx, const llvm::APInt &v, CompilerType type, llvm::StringRef name, ValueObject *parent=nullptr)
	Create a value object containing the given APInt value.
static lldb::ValueObjectSP	CreateValueObjectFromAPFloat (const ExecutionContext &exe_ctx, const llvm::APFloat &v, CompilerType type, llvm::StringRef name, ValueObject *parent=nullptr)
	Create a value object containing the given APFloat value.
static lldb::ValueObjectSP	CreateValueObjectFromScalar (const ExecutionContext &exe_ctx, Scalar &s, CompilerType type, llvm::StringRef name, ValueObject *parent=nullptr)
	Create a value object containing the given Scalar value.
static lldb::ValueObjectSP	CreateValueObjectFromBool (const ExecutionContext &exe_ctx, lldb::TypeSystemSP typesystem, bool value, llvm::StringRef name, ValueObject *parent=nullptr)
	Create a value object containing the given boolean value.
static lldb::ValueObjectSP	CreateValueObjectFromNullptr (const ExecutionContext &exe_ctx, CompilerType type, llvm::StringRef name, ValueObject *parent=nullptr)
	Create a nullptr value object with the specified type (must be a nullptr type).

Protected Member Functions
bool	UpdateValue () override
void	DoUpdateChildrenAddressType (ValueObject &valobj) override
CompilerType	GetCompilerTypeImpl () override
Protected Member Functions inherited from lldb_private::ValueObject
	ValueObject (ExecutionContextScope *exe_scope, ValueObjectManager &manager, AddressType child_ptr_or_ref_addr_type=eAddressTypeLoad)
	Use this constructor to create a "root variable object".
	ValueObject (ValueObject &parent)
	Use this constructor to create a ValueObject owned by another ValueObject.
ValueObjectManager *	GetManager ()
virtual LazyBool	CanUpdateWithInvalidExecutionContext ()
virtual void	CalculateDynamicValue (lldb::DynamicValueType use_dynamic)
virtual lldb::DynamicValueType	GetDynamicValueTypeImpl ()
virtual bool	HasDynamicValueTypeInfo ()
virtual void	CalculateSyntheticValue ()
virtual ValueObject *	CreateChildAtIndex (size_t idx)
	Should only be called by ValueObject::GetChildAtIndex().
virtual ValueObject *	CreateSyntheticArrayMember (size_t idx)
	Should only be called by ValueObject::GetSyntheticArrayMember().
void	SetNumChildren (uint32_t num_children)
void	SetValueDidChange (bool value_changed)
void	SetValueIsValid (bool valid)
void	ClearUserVisibleData (uint32_t items=ValueObject::eClearUserVisibleDataItemsAllStrings)
void	AddSyntheticChild (ConstString key, ValueObject *valobj)
DataExtractor &	GetDataExtractor ()
void	ClearDynamicTypeInformation ()
const char *	GetLocationAsCStringImpl (const Value &value, const DataExtractor &data)
bool	IsChecksumEmpty ()
void	SetPreferredDisplayLanguageIfNeeded (lldb::LanguageType)

Protected Attributes
lldb::VariableSP	m_variable_sp
	The variable that this value object is based upon.
Value	m_resolved_value
	The value that DWARFExpression resolves this variable to before we patch it up.
Protected Attributes inherited from lldb_private::ValueObject
ValueObject *	m_parent = nullptr
	The parent value object, or nullptr if this has no parent.
ValueObject *	m_root = nullptr
	The root of the hierarchy for this ValueObject (or nullptr if never calculated).
EvaluationPoint	m_update_point
	Stores both the stop id and the full context at which this value was last updated.
ConstString	m_name
	The name of this object.
DataExtractor	m_data
	A data extractor that can be used to extract the value.
Value	m_value
Status	m_error
	An error object that can describe any errors that occur when updating values.
std::string	m_value_str
	Cached value string that will get cleared if/when the value is updated.
std::string	m_old_value_str
	Cached old value string from the last time the value was gotten.
std::string	m_location_str
	Cached location string that will get cleared if/when the value is updated.
std::string	m_summary_str
	Cached summary string that will get cleared if/when the value is updated.
std::string	m_object_desc_str
	Cached result of the "object printer".
CompilerType	m_override_type
	If the type of the value object should be overridden, the type to impose.
ValueObjectManager *	m_manager = nullptr
	This object is managed by the root object (any ValueObject that gets created without a parent.) The manager gets passed through all the generations of dependent objects, and will keep the whole cluster of objects alive as long as a shared pointer to any of them has been handed out.
ChildrenManager	m_children
std::map< ConstString, ValueObject * >	m_synthetic_children
ValueObject *	m_dynamic_value = nullptr
ValueObject *	m_synthetic_value = nullptr
ValueObject *	m_deref_valobj = nullptr
lldb::ValueObjectSP	m_addr_of_valobj_sp
	We have to hold onto a shared pointer to this one because it is created as an independent ValueObjectConstResult, which isn't managed by us.
lldb::Format	m_format = lldb::eFormatDefault
lldb::Format	m_last_format = lldb::eFormatDefault
uint32_t	m_last_format_mgr_revision = 0
lldb::TypeSummaryImplSP	m_type_summary_sp
lldb::TypeFormatImplSP	m_type_format_sp
lldb::SyntheticChildrenSP	m_synthetic_children_sp
ProcessModID	m_user_id_of_forced_summary
AddressType	m_address_type_of_ptr_or_ref_children = eAddressTypeInvalid
llvm::SmallVector< uint8_t, 16 >	m_value_checksum
lldb::LanguageType	m_preferred_display_language = lldb::eLanguageTypeUnknown
uint64_t	m_language_flags = 0
UserID	m_id
	Unique identifier for every value object.
struct lldb_private::ValueObject::Bitflags	m_flags

Private Member Functions
	ValueObjectVariable (ExecutionContextScope *exe_scope, ValueObjectManager &manager, const lldb::VariableSP &var_sp)
	ValueObjectVariable (const ValueObjectVariable &)=delete
const ValueObjectVariable &	operator= (const ValueObjectVariable &)=delete

Additional Inherited Members
Public Types inherited from lldb_private::ValueObject
enum	GetExpressionPathFormat { eGetExpressionPathFormatDereferencePointers = 1 , eGetExpressionPathFormatHonorPointers }
enum	ValueObjectRepresentationStyle { eValueObjectRepresentationStyleValue = 1 , eValueObjectRepresentationStyleSummary , eValueObjectRepresentationStyleLanguageSpecific , eValueObjectRepresentationStyleLocation , eValueObjectRepresentationStyleChildrenCount , eValueObjectRepresentationStyleType , eValueObjectRepresentationStyleName , eValueObjectRepresentationStyleExpressionPath }
enum	ExpressionPathScanEndReason { eExpressionPathScanEndReasonEndOfString = 1 , eExpressionPathScanEndReasonNoSuchChild , eExpressionPathScanEndReasonNoSuchSyntheticChild , eExpressionPathScanEndReasonEmptyRangeNotAllowed , eExpressionPathScanEndReasonDotInsteadOfArrow , eExpressionPathScanEndReasonArrowInsteadOfDot , eExpressionPathScanEndReasonFragileIVarNotAllowed , eExpressionPathScanEndReasonRangeOperatorNotAllowed , eExpressionPathScanEndReasonRangeOperatorInvalid , eExpressionPathScanEndReasonArrayRangeOperatorMet , eExpressionPathScanEndReasonBitfieldRangeOperatorMet , eExpressionPathScanEndReasonUnexpectedSymbol , eExpressionPathScanEndReasonTakingAddressFailed , eExpressionPathScanEndReasonDereferencingFailed , eExpressionPathScanEndReasonRangeOperatorExpanded , eExpressionPathScanEndReasonSyntheticValueMissing , eExpressionPathScanEndReasonUnknown = 0xFFFF }
enum	ExpressionPathEndResultType { eExpressionPathEndResultTypePlain = 1 , eExpressionPathEndResultTypeBitfield , eExpressionPathEndResultTypeBoundedRange , eExpressionPathEndResultTypeUnboundedRange , eExpressionPathEndResultTypeValueObjectList , eExpressionPathEndResultTypeInvalid = 0xFFFF }
enum	ExpressionPathAftermath { eExpressionPathAftermathNothing = 1 , eExpressionPathAftermathDereference , eExpressionPathAftermathTakeAddress }
enum	ClearUserVisibleDataItems { eClearUserVisibleDataItemsNothing = 1u << 0 , eClearUserVisibleDataItemsValue = 1u << 1 , eClearUserVisibleDataItemsSummary = 1u << 2 , eClearUserVisibleDataItemsLocation = 1u << 3 , eClearUserVisibleDataItemsDescription = 1u << 4 , eClearUserVisibleDataItemsSyntheticChildren = 1u << 5 , eClearUserVisibleDataItemsAllStrings , eClearUserVisibleDataItemsAll = 0xFFFF }
enum class	PrintableRepresentationSpecialCases : bool { eDisable = false , eAllow = true }
Protected Types inherited from lldb_private::ValueObject
typedef ClusterManager< ValueObject >	ValueObjectManager
using	ValueObjectManagerSP = std::shared_ptr<ValueObjectManager>
Static Protected Member Functions inherited from lldb_private::ValueObject
static ValueObjectManagerSP	ReuseManagerIfParent (ValueObject *parent)
	The following two functions are helpers for Create methods for ValueObject subclasses that need to optionally receive a parent or external manager.
static ValueObjectManagerSP	CreateManagerIfEmpty (ValueObjectManager *&manager)
	If manager is null, makes a new ValueObjectManager and sets manager to the new ValueObjectManager.