xref: /freebsd/contrib/lutok/examples/hello.cpp (revision 19fae0f66023a97a9b464b3beeeabb2081f575b3)
1 // Copyright 2012 Google Inc.
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28 
29 /// \file examples/hello.cpp
30 /// Minimal example using Lua code to print a traditional hello-world message.
31 
32 #include <cstdlib>
33 
34 #include <lutok/state.ipp>
35 
36 
37 /// Program's entry point.
38 ///
39 /// \return A system exit code.
40 int
41 main(void)
42 {
43     // Initializes a new Lua state.  Every Lua state is independent from each
44     // other.
45     lutok::state state;
46 
47     // Loads the standard library into the Lua state.  Among many other
48     // functions, this gives us access to print(), which is used below.
49     state.open_base();
50 
51     // Pushes the print() function into the Lua stack, then its only argument,
52     // and then proceeds to execute it within the Lua state.
53     state.get_global("print");
54     state.push_string("Hello, world!");
55     state.pcall(1, 0, 0);
56 
57     return EXIT_SUCCESS;
58 }
59