static int luaB_coresume (lua_State *L) {
lua_State *co = lua_tothread(L, 1);
int r;
luaL_argcheck(L, co, 1, "coroutine expected");
r = auxresume(L, co, lua_gettop(L) - 1);
if (r < 0) {
lua_pushboolean(L, 0);
lua_insert(L, -2);
return 2; /* return false + error message */
}
else {
lua_pushboolean(L, 1);
lua_insert(L, -(r + 1));
return r + 1; /* return true + `resume' returns */
}
}
static int luaB_auxwrap(lua_State* L)
{
lua_State* co = lua_tothread(L, lua_upvalueindex(1));
int r = auxresume(L, co, lua_gettop(L));
if (r < 0)
{
if (lua_isstring(L, -1)) /* error object is a string? */
{
luaL_where(L, 1); /* add extra info */
lua_insert(L, -2);
lua_concat(L, 2);
}
lua_error(L); /* propagate error */
}
return r;
}