lua Namespace Reference

Every thing in Lua API++ library is contained inside this namespace. More...

Classes
struct	ClosureInfo
	Closure properties. [Lua 5.2+ only] More...
class	Context
	Access point to Lua context. More...
class	Nil
	Type of nil value. More...
class	RegistryKey
	Key for registry-stored values. More...
class	Retval
	Return value for Lua functions. More...
class	State
	Lua state object. More...
class	Table
	Table object with specialized interface. Similar to Value, it owns a stack slot. More...
class	Temporary
	Temporary Lua value. More...
struct	TypeID
	Determine Lua type ID from native type. More...
class	Valobj
	Lua-compatible value. More...
class	Valref
	Non-owning reference to Lua value. More...
class	Valset
	Valset is an STL-compatible container for contiguous Lua stack slots. Its primary use is accepting multiple return values. More...
class	Value
	Owner of a single stack slot. More...

Typedefs
using	LFunction = Retval(*)(Context &)
	Pointer to Lua API++ compatible function. More...
using	CFunction = int(*)(lua_State *)
	C function callable by Lua (plain Lua API format). More...
typedef void *	LightUserData
	Light userdata. More...

Enumerations
enum	ValueType {   None = -1, Nil, Boolean, LightUserdata,   Number, String, Table, Function,   C_Function, UserData, Thread, Any }
	Types of Lua values. More...

Functions
template<LFunction F>
int	mkcf (lua_State *l)
	Wrapper for LFunction that creates a proper Lua-compatible C function. More...

Variables
static constexpr Nil	nil {}
	Constant representing nil value. More...

Detailed Description

Every thing in Lua API++ library is contained inside this namespace.

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Class Documentation

struct lua::ClosureInfo

Closure properties. [Lua 5.2+ only]

See also

lua::Valref::getClosureInfo

Class Members
size_t	nUpvalues	Amount of upvalues.
size_t	nParameters	Amount of parameters.
bool	variadic	Whether function accepts variable number of arguments.

class lua::Nil

Type of nil value.

This type can be used in type checks with function is.

class lua::Temporary

Temporary Lua value.

This is not an actual type, see the explanation.

See also

lua::Valref

class lua::Valobj

Lua-compatible value.

This is not an actual type, it designates any type of value that is or can become a Lua value: references to Lua stack, temporaries, native numbers and strings, userdata etc.

Typedef Documentation

typedef Retval(* LFunction)(Context &)

Pointer to Lua API++ compatible function.

Lua-API++ compatible function.

See also

lua::mkcf

using CFunction = int (*)(lua_State*)

C function callable by Lua (plain Lua API format).

See also

lua::mkcf

typedef void* LightUserData

Light userdata.

This typedef is provided for explicit designation of light userdata.

Enumeration Type Documentation

enum ValueType

strong

Types of Lua values.

This enum is used to identify actual types of Lua values both in compile-time and runtime.

Enumerator
None	not a Lua value
Nil	absence of data
Boolean	boolean
LightUserdata	light userdata
Number	number
String	string
Table	table
Function	Lua function.
C_Function	Lua-compatible C function.
UserData	full userdata
Thread	Lua documentation names this object "coroutine", but Lua API names it "thread".
Any	Lua value with content type indeterminable at the time of query.

Function Documentation

int lua::mkcf

(

lua_State *

l

)

Wrapper for LFunction that creates a proper Lua-compatible C function.

template<LFunction F> mkcf
This template converts Lua API++ compatible function to a proper Lua-compatible C function (mkcf is short for "make C function"). The wrapper creates Context object and passes it to wrapped function, then converts returned Retval to number of returned values. All exceptions that come from wrapped function are intercepted and converted to Lua runtime errors. Example:

Retval someFunction(Context& context) {return context.ret();}
CFunction cf = mkcf<someFunction>;

Note the lack of round parentheses when using mkcf template.

Note

Unlike closure function, mkcf creates individual wrapper for each LFunctions. It doesn't reserve first upvalue for internal use.

Variable Documentation

constexpr Nil nil {}

static

Constant representing nil value.

Note

It is possible to check values for emptiness by comparing (equality or inequality) against nil value, but is<Nil>() is more efficient.