Luabind for sin math function

First we register the cmath sin() function as a function named sin() in Lua:

	#include <iostream>
	#include <luabind/luabind.hpp>
	#include <cmath>
	extern "C" int init(lua_State* L)
	{
	using namespace luabind;
	open(L);
	module(L)
	[
	def("sin", (float(*)(float)) &std::sin)
	];
	return 0;
	}

view raw sin.cpp hosted with ❤ by GitHub

We write a simple script to test the Lua sin() function:

kuyu@castor-ub:~/dkuyu/Dropbox/practice/lua/luabind/sin$ cat test.lua 
package.loadlib('./c.so', 'init')()
print(sin(1.57))

We compile and test it as follows:

kuyu@castor-ub:~/dkuyu/Dropbox/practice/lua/luabind/sin$ cat commands.bash 

#!/bin/bash

g++ c.cpp -I/usr/include/lua5.2/ -c -fPIC

g++ -shared -Wl,--whole-archive -o c.so c.o -lluabind -Wl,--no-whole-archive

lua test.lua

kuyu@castor-ub:~/dkuyu/Dropbox/practice/lua/luabind/sin$ ./commands.bash 

0.99999970197678

(1.57 is very close to pi/2 and the sin of pi/2 is 1.)