Understanding Clojure's Persistent Vectors, pt. 1 (2013)
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HN comment orderIMHO, this is one of the coolest aspects of Clojure: the data structures were designed to be immutable as efficiently as possible. This allows for some of the most critical aspects of the language to function. If you're whole program passes around values that are immutable, you don't ever have to worry about which part of the code owns what. Rust is such a different language but the borrow-checker is solving a nearly identical problem: who owns this memory and…
Does anyone have benchmarks comparing the performance of Clojure's PersistentVectors to standard arrays in Java and/or C? O(1) is pretty useless if the constant factor is huge. Anecdotally, I've heard that they are "fast" but it would be interesting to know what that really means.
Persistent data structures are, in my opinion, underrated. Not so much for every day programming tasks, but specifically for code that resembles planning/searching. Here is one library I've heard of https://immutable-js.com/ . I don't know of others.
Related from 2014: https://news.ycombinator.com/item?id=8503912 Discussed at the time: https://news.ycombinator.com/item?id=6445628
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