A DatumRef object is a read-only reference to an C++ object of a supported runtime type. More...

#include <base/datum.h>

Inheritance diagram for taco::DatumRef:

Public Member Functions
	DatumRef (const Datum &d)

	DatumRef (const DatumRef &)=default

DatumRef &	operator= (const DatumRef &)=default

constexpr bool	isnull () const

Public Member Functions inherited from taco::datum_impl::DatumRefVarlenGetters< DatumRef >
constexpr const char *	GetVarlenBytes () const
	Returns the variable-length value of a datum as an array of bytes. More...

constexpr uint32_t	GetVarlenSize () const
	Returns the length of the variable-length value of a datum. More...

constexpr absl::string_view	GetVarlenAsStringView () const

constexpr Datum &	GetDatum () const
	Returns a reference to the underlying datum if this references one with a variable-length value. More...

Datum	DeepCopy (bool isbyref) const
	Returns a new Datum that is a deep copy of the underlying datum. More...

Protected Member Functions
	DatumRef (datum_impl::DatumRep val)

Protected Attributes
datum_impl::DatumRep	m_val

Friends
class	datum_impl::NonVarlenGetters< DatumRef >

class	NullableDatumRef

Detailed Description

A DatumRef object is a read-only reference to an C++ object of a supported runtime type.

There is an implicit conversion from a Datum to DatumRef so that one may use a Datum variable where it needs a DatumRef. The object referenced by a DatumRef is always assumed to be non-null.

DatumRef makes a copy of the actual value stored in its referencing Datum unless the value is variable length with the length field (i.e., the pointer to a null-terminated string still get copied into a DatumRef). In the case that the value is a variable length field, DatumRef stores a pointer to the referencing Datum, which requires an additional indirection when read. Note that the nullness of the referencing Datum is always ignored, even if we store a pointer here.

Constructor & Destructor Documentation

◆ DatumRef() [1/3]

taco::DatumRef::DatumRef ( const Datum & d )

inline

◆ DatumRef() [2/3]

taco::DatumRef::DatumRef ( const DatumRef & )

default

◆ DatumRef() [3/3]

taco::DatumRef::DatumRef ( datum_impl::DatumRep val )

inlineprotected

Member Function Documentation

◆ isnull()

constexpr bool taco::DatumRef::isnull ( ) const

inlineconstexpr

◆ operator=()

DatumRef& taco::DatumRef::operator= ( const DatumRef & )

default

Friends And Related Function Documentation

◆ datum_impl::NonVarlenGetters< DatumRef >

friend class datum_impl::NonVarlenGetters< DatumRef >

friend

◆ NullableDatumRef

friend class NullableDatumRef

friend

Member Data Documentation

◆ m_val

datum_impl::DatumRep taco::DatumRef::m_val

protected

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

base/datum.h

Public Member Functions

Protected Member Functions

Protected Attributes

Friends