Using LUA interaction in C + +, Lua implements closures, C++/lua mutual closures

Lua is a configuration file artifact, specific features used to know, nearly two years useless smoked two hours familiar with the next basic usage.

Includes C/lua stack operation function calls to each other and LUA closures for C + + and LUA closures

To be flexible with LUA, it is interesting to learn that the stack interaction model of LUA and C is similar to the way assembly functions are called.

To learn Lua, first understand the stacks of LUA and C + + interactions lua_state Here is a very detailed article citing netizens

http://wind-catalpa.blog.163.com/blog/static/1147535432013119103150929/

On the Code

C + + code

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<span style= "Font-size:14px;color: #000000;" > #include "string.h" extern "C" {#include "lualib.h"//contains LUA lib#include "lauxlib.h"//auxiliary function}; #pragma comment (lib, "Lua . Lib ")//lua and C programs Exchange data through a stack: lua_statelua_state* Getlua () {lua_state* lu = lual_newstate ();/* Create LUA Objects */Lual_openlibs (LU ); Open all shared library functions to the Lua object return LU;} Bulk data pressed into stack # define For_push (I,j,step,lua) for (int i=i;i<=j;i+=step) {Lua_pushinteger (lua,i);} Take out the data//print stack data for the specified index in the stack # # for_list (I,j,step,lua) for (int i=i;i<=j;i+=step) {int N=lua  _tointeger (Lua,i);   printf ("Stack index:%d, Data:%d\n", i,n); } #define CLEAR (LUA) for (int i=1;i<=lua_gettop (LUA); i++) Lua_pop (lua,i)//return 1 Results//function prototype specific reference LUA5.2 document INT Callcpp (LU    A_state *lua) {int a = Lua_tointeger (LUA, 1);    int b = Lua_tointeger (LUA, 2);    Lua_pushnumber (LUA, a+b);             Result press stack return 1; } int _tmain (int argc, _tchar* argv[]) {//Get stack pointer for C and LUA interaction lua_state *lua =getlua (); if (lua==nullptr) {printf ("Lua Open Error"); return 0;} The stack operation for Lua For_push (1,10,1,lua);//the parameter int n=lua_gettop (LUA) that loops sequentially into the stack;p rintf ("%d arguments \ n" in the Lua stack); For_list (1,10,1,lua); Lua_pop (lua,3);//pops up three parameters N=lua_gettop (LUA);p rintf ("%d parameters \ n" in the Lua stack) in a stack LIFO mode; For_list (1,n,1,lua);  Executes the simple memory Lua script char*plua= "print (\" hello,lua!\ ")"; Lual_loadbuffer (Lua,plua,strlen (Plua), "Testluascript0chunk"), if (Lua_ok==lua_pcall (LUA, 0,0,0)) {printf ("Lua Script call succeeded!\n ");} pops up stack all data clear (LUA),/////Load Lua script and compile run LUA script//load from current working directory if (Lual_dofile (Lua, "./c.lua")) {printf ("Lua script loaded successfully!\n");} Lua_getglobal (LUA, "NUM1");//load to stack Lua_getglobal (LUA, "num2");//load to stack Lua_getglobal (LUA, "str1");    Load string int num1 = Lua_tointeger (LUA,-3); The inverse value from the stack Lua stack is bidirectional printf ("num1:%d\n", NUM1); N=lua_gettop (LUA);    int num2 = Lua_tointeger (Lua,-2); The inverse value from the stack Lua stack is bidirectional printf ("num2:%d\n", num2); N=lua_gettop (LUA); printf (there are%d parameters \ n in the LUA stack); CLEAR (LUA); The load function to the stack//call is the parameterless function Lua_getglobal (LUA, "Testhello"); N=lua_gettop (LUA); printf (there are%d parameters \ n in the LUA stack); The LUA function call automatically cleans up the stack lua_pcall (LUA, 0,0,0); N=lua_gettop (LUA); printf (there are%d parameters \ n in the LUA stack); Lua_getglobal (LUA, "Closer"); The function is pressed into the stack top Lua_pushinteger (lua,1); Lua_pushinteger (lua,2);//press-in Parameter//closure function call if (Lua_ok!=lua_pcall (lua,2,1,0)) {printf ("function call failed!\n"); return 0;} int result=l Ua_tointeger (lua,-1);//Remove the stack top data printf ("Closer result:%d\n", result); Note Clean up the stack return value at the top of the stack pop Lua_pop (lua,1); N=lua_gettop (LUA); printf (there are%d parameters \ n in the LUA stack); LUA calls C + + functions//Registration Functions Lua_register (LUA, "CALLC", callcpp); Loads the IF (Lual_dofile (Lua, "./c1.lua")) {printf ("Lua C1 script load succeeded!\n") from the current working directory;///c/lua closure calls Lua_pushcfunction (lua,callcpp ); Lua_setglobal (LUA, "CALLCT");//Set Call Lua_getglobal (LUA, "Closert") in Lua,//Load LUA closure function to C + + stack Lua_pushinteger (lua,2); The function stack parameter must be correct Lua_pushinteger (lua,3), Lua_pcall (lua,2,0,0), N=lua_gettop (LUA);p rintf ("%d arguments \ n" in the Lua stack); return 0;} </span>

C. Lua and C1.lua files

--c.lua

str1= "Hello,i am Luaer" num1=2num2=3--test function output str1function Testhello ()   print (STR1) End--lua implement closure function  Closer (I,J)   function Add (i,j)      return i+j   end   return Add (i,j) endfunction CALLC (A, b)  return Callcpp (A, B) end

--c1.lua Call C + + FUNCTIONNUM=CALLC (3,4) print ("num is:", num)--c++ and LUA mutual closure function Closert (A, B)    num1=callct (A, B)    print ("C++/lua Mutual closure Num1 is:", NUM1) end

Using LUA interaction in C + +, Lua implements closures, C++/lua mutual closures