Function lua_compare

extlibs/sol3/include/sol/sol.hpp:2537–2559

"return a<=b\n";

COMPAT53_API int lua_compare(lua_State *L, int idx1, int idx2, int op) {
	int result = 0;
	switch (op) {
	case LUA_OPEQ:
		return lua_equal(L, idx1, idx2);
	case LUA_OPLT:
		return lua_lessthan(L, idx1, idx2);
	case LUA_OPLE:
		luaL_checkstack(L, 5, "not enough stack slots");
		idx1 = lua_absindex(L, idx1);
		idx2 = lua_absindex(L, idx2);
		lua_pushvalue(L, idx1);
		lua_pushvalue(L, idx2);
		compat53_call_lua(L, compat53_compare_code,
			sizeof(compat53_compare_code) - 1, 2, 1);
		result = lua_toboolean(L, -1);
		lua_pop(L, 1);
		return result;
	default:
		luaL_error(L, "invalid 'op' argument for lua_compare");
	}
	return 0;
}

COMPAT53_API void lua_copy(lua_State *L, int from, int to) {
	int abs_to = lua_absindex(L, to);