A true pure function combined with persistent immutable data structures (Immutable.js, Clojure, Scala, et al) can be memoized and re-executed practically for free (in very short constant time).
P.S. In React for example, in almost all cases the amount of memory dedicated to holding immutable data is typically tiny for modern hardware. So it almost always makes sense to trade memory for faster execution.
P.S. In React for example, in almost all cases the amount of memory dedicated to holding immutable data is typically tiny for modern hardware. So it almost always makes sense to trade memory for faster execution.