From the headline alone, I guessed this was to do with pointers/references to values vs values themselves.<p>Yep, with values that take a lot of memory, it's faster to pass pointers/references around than it is to pass the values around, because it is less bytes to copy.<p>Of course there is more to such a decision than just performance, because if the code makes changes to the value which are not meant to be persisted, then one wants to be working with a copy of the value, not a pointer to the value. So one should take care if simply switching some code from values to pointers-to-values.<p>All of these things are things that coders with more experience of languages that use such semantics kinda know already, almost as second nature, since the first day they got caught out by them. But everyone is learning, to various degrees, and we all have to start somewhere (i.e. knowing little to nothing).