[odb-users] std::transform changes the begin iterator

[Zhao Xiang]

Dear ODB support,


I'm currently using odb 2.4.0, and I think I've found a bug with odb::result and std::transform.


My code is like below:


odb::result<user_player> players = db.query<user_player>(...);


std::vector<uint32_t> playerIds;
playerIds.resize(players.size());
std::transform(players.begin(), players.end(), playerIds.begin(), [](const user_player& p)
{
	return p.key.player_id;
});


assert(players.size() > 0);//ok
assert(players.begin() != players.end());//oops



After some debug I noticed the value of players.begin() is changed after the std::transform call.


So I think this is a bug in odb's iterator implementation.


Regards
Zhao Xiang