How to make a new function and pass it through another function

Question

Basically I don't know how to do something like that:

    lua_pushcfunction(L, int func(lua_State* L) { 
      printf("hello");
      return 0;
    });

I have tried many stuff but doesnt just work

Possible duplicate: https://stackoverflow.com/questions/9410/how-do-you-pass-a-function-as-a-parameter-in-c — alter_igel, Mar 07 '19 at 22:43
not what I mean, they create functions then pass them and I want to do it the way there — Void E, Mar 07 '19 at 22:44
Perhaps you need [lambda expressions](https://stackoverflow.com/questions/7627098/what-is-a-lambda-expression-in-c11)? — alter_igel, Mar 07 '19 at 22:45

score 2 · Answer 1 · answered Mar 07 '19 at 23:42

Two ways:

Define the function then push it.

int func(lua_State* L) { 
  printf("hello");
  return 0;
};

// later...
lua_pushcfunction(L, func);

This is the only way you could do it in C, or before C++11.

Use a lambda expression (aka. anonymous function):

lua_pushcfunction(L, [](lua_State* L) -> int { 
  printf("hello");
  return 0;
});

1 Answers1