> Avoiding shared state mutation isn't especially hard in imperative languages You're right, it isn't, and I wasn't trying to claim it was a particularly big p

> Avoiding shared state mutation isn't especially hard in imperative languages You're right, it isn't, and I wasn't trying to claim it was a particularly big problem. What it is is another little you don't even have to think about which I found to be a pretty delightful feeling. Cloning isn't a consideration in mutable languages and that's a nice a little win. Though as a sibling comment mentions, if you're working with a bunch of inexperienced folk, these things are a lot more likely to slip through. As for the debugging bit, I made the sin of comment before I read the article and realized it was using JS. No matter what anyone wants to tell you, JS is very good as a functional language. It can be ok, but it's not great. "Most functional styles" is otherwise a very unfair statement as most functional languages come with pipes or infix application operators that make debugging really easy as you can throw an `inspect` into a pipeline. Getting a bit off the rails just as I was excited about this, but Elixir recently introduced a `dbg` function which, if used at the end of a pipeline, outputs every line of it which is crazy nice (unsure if this was borrowed from another language or not): "hello there" |> String.split() |> IO.inspect() |> Enum.map(&String.capitalize/1) |> Enum.join(" ") |> dbg() produces: [file_name.ex:8: ModuleName.function_name/0] "hello there" #=> "hello there" |> String.split() #=> ["hello", "there"] |> IO.inspect() #=> ["hello", "there"] |> Enum.map(&String.capitalize/1) #=> ["Hello", "There"] |> Enum.join(" ") #=> "Hello There" So that's really nice.