Using Lua API and tag method facilities, tolua maps C/C++ constants, external variables, functions, classes, and methods to Lua.

(1)创建a package file (a C/C++ cleaned header file) listing the constants, variables, functions, classes, and methods we want to export to the Lua environment.

(2)parses this file and creates a C/C++ file that automatically binds the C/C++ code to Lua. 

(3) accesed from Lua

由(1)an executable (2)and a library组成

the executable represents the parser that reads a package file and output a C/C++ code that implements the binding to access the C/C++ features from Lua.

tolua -o myfile.c myfile.pkg

tolua -n pkgname -o myfile.c myfile.pkg

when using C++, we can opt for automatic initialization

tolua -a -n pkgname -o myfile.c myfile.pkg

automatic initialization sometimes does not work

也能够调用tolua_pkgname_close(void);解绑

能够使用-H选项将open与close操作导出到头文件里。

void tolua_restorestate (void);

package file may include other package file, use $<include_file>

char int float double     ->       number

char*       ->              string

void*       ->              userdata

tolua ignores const modifier

Functions in C/C++ can also manipulate Lua objects explicitly.

lua_Object也是一种基本类型。

非Basic Types均为用户自己定义类型，are mapped to tagged userdata type in Lua.

Lua can only store pointers to 自己定义类型。