#[unsafe(no_mangle)]pub unsafe extern "C" fn luaL_optnumber(
L: *mut lua_State,
idx: c_int,
def: lua_Number,
) -> lua_Number#[unsafe(no_mangle)]pub unsafe extern "C" fn luaL_optnumber(
L: *mut lua_State,
idx: c_int,
def: lua_Number,
) -> lua_Number