Generally, most logging frameworks have two parts, the format string, and the parameters. A good logging library will also avoid calling str()/toString() if the

Generally, most logging frameworks have two parts, the format string, and the parameters. A good logging library will also avoid calling str()/toString() if the log isn't emitted (for example, if it's a debug log but minimum level is info). You have something similar when building database queries, generally you should have a base template into which you insert arguments. The library generally should take care of escaping things and also preventing things like SQL injections.