dmlc::LuaRef Class Reference

an reference to lua object More...

#include <lua.h>

Public Member Functions
	LuaRef ()=default
	construct an nil ref
	LuaRef (LuaRef &&other)
	move constructor from another LuaRef
	LuaRef (const LuaRef &other)
	copy constructor
LuaRef &	operator= (LuaRef &&other)
	assign operator from other
LuaRef &	operator= (const LuaRef &other)
	assign operator from other
	~LuaRef ()
	destructor
void	swap (LuaRef &other)
	swap content with another ref
template<typename T >
T	Get () const
	Get content out as type T.
template<typename T >
T *	GetUDataPtr () const
	Get user data pointer from LuaRef.
bool	is_nil () const
template<typename... Args>
LuaRef	operator() (Args &&...args) const
	invoke the LuaRef as function
LuaRef	operator[] (const std::string &key) const
	Get field from the lua table. The reference must be a table.
LuaRef	operator[] (size_t index) const
	Get field from the lua array The reference must be a array.
template<typename T >
LuaRef &	SetField (const std::string &key, const T &value)
	Set field of lua table. The reference must be a table.
void	SetByPopStack_ (LuaState *s)
	Set LuaRef to the value on top of the stack. This state must be nil. This is API used by developer.

Friends
struct	lua_stack::Handler< LuaRef >
class	LuaState
std::ostream &	operator<< (std::ostream &os, const LuaRef &r)

Detailed Description

an reference to lua object

Constructor & Destructor Documentation

LuaRef() [1/2]

dmlc::LuaRef::LuaRef ( LuaRef &&  other )

inline

move constructor from another LuaRef

Parameters

other

The other LuaRef to be moved

LuaRef() [2/2]

dmlc::LuaRef::LuaRef ( const LuaRef &  other )

inline

copy constructor

Parameters

other

The other LuaRef to be copied

Member Function Documentation

Get()

template<typename T >

T dmlc::LuaRef::Get ( ) const

inline

Get content out as type T.

Template Parameters

T	the type to be fetched.

Returns

the corresponding c type.

GetUDataPtr()

template<typename T >

T * dmlc::LuaRef::GetUDataPtr ( ) const

inline

Get user data pointer from LuaRef.

CAREFUL when getting userdata(e.g. pointer to Tensor's storage) from LuaRef. Remember they are managed by Lua, and can get deleted when all the LuaRef to the userdata destructs. A good practice is always use a LuaRef to keep the userdata alive when you need them from C++ side.

Template Parameters

T	the type of pointer to be fetched.

Returns

the corresponding c type.

is_nil()

bool dmlc::LuaRef::is_nil ( ) const

inline

Returns

whether the value is nil

operator()()

template<typename... Args>

LuaRef dmlc::LuaRef::operator() ( Args &&...  args ) const

inline

invoke the LuaRef as function

Parameters

args	Arguments to be passed.

Template Parameters

Args	arguments to be passed.

Returns

The first return value.

operator=() [1/2]

LuaRef & dmlc::LuaRef::operator= ( const LuaRef &  other )

inline

assign operator from other

Parameters

other

The other LuaRef to be copy or moved.

Returns

self

operator=() [2/2]

LuaRef & dmlc::LuaRef::operator= ( LuaRef &&  other )

inline

assign operator from other

Parameters

other

The other LuaRef to be copy or moved.

Returns

self

operator[]() [1/2]

LuaRef dmlc::LuaRef::operator[] ( const std::string &  key ) const

inline

Get field from the lua table. The reference must be a table.

Parameters

key	The key to the table

Returns

a new ref to the corresponding field.

operator[]() [2/2]

LuaRef dmlc::LuaRef::operator[] ( size_t  index ) const

inline

Get field from the lua array The reference must be a array.

Parameters

index

The index to the array, Note: the index convention follows lua table, starts from 1

Returns

a new ref to the corresponding field.

SetByPopStack_()

void dmlc::LuaRef::SetByPopStack_ ( LuaState *  s )

inline

Set LuaRef to the value on top of the stack. This state must be nil. This is API used by developer.

Parameters

s	the corresponding lua state.

SetField()

template<typename T >

LuaRef & dmlc::LuaRef::SetField ( const std::string &  key, const T &  value  )

inline

Set field of lua table. The reference must be a table.

Parameters

key	The key to the table
value	Lua convertable value to be setted.

Returns

self.

swap()

void dmlc::LuaRef::swap ( LuaRef &  other )

inline

swap content with another ref

Parameters

other

another LuaRef to be swaped.

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

• External/xgboost/dmlc-core/include/dmlc/lua.h