HardenedBSD/contrib/lutok/examples/hello.cpp
Brooks Davis c697fb7f7c Add liblutok a lightweight C++ API for lua.
It is added an INTERNALLIB and not installed.  It will be used by kyua.

This is a preparatory commit for D24103.

Reviewed by:	emaste
Obtained from:	CheriBSD
Sponsored by:	DARPA
2020-03-23 18:26:23 +00:00

59 lines
2.3 KiB
C++

// Copyright 2012 Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
// * Neither the name of Google Inc. nor the names of its contributors
// may be used to endorse or promote products derived from this software
// without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
/// \file examples/hello.cpp
/// Minimal example using Lua code to print a traditional hello-world message.
#include <cstdlib>
#include <lutok/state.ipp>
/// Program's entry point.
///
/// \return A system exit code.
int
main(void)
{
// Initializes a new Lua state. Every Lua state is independent from each
// other.
lutok::state state;
// Loads the standard library into the Lua state. Among many other
// functions, this gives us access to print(), which is used below.
state.open_base();
// Pushes the print() function into the Lua stack, then its only argument,
// and then proceeds to execute it within the Lua state.
state.get_global("print");
state.push_string("Hello, world!");
state.pcall(1, 0, 0);
return EXIT_SUCCESS;
}