In general you can't mutate records. Nothing prevents you from making a new one that's slightly different though. It just won't change the already existing one.

In general you can't mutate records. Nothing prevents you from making a new one that's slightly different though. It just won't change the already existing one. In practice this is not actually a problem. It just takes a little getting used to to get yourself out of the 'memory-address as identity' mindset that procedural languages have.