[treeform]

Mutating in place is often times faster and is more straightforward.

I do feel Nim embraces mutation more than other recent languages.

[eindiran]

Yeah, the 'discard' keyword is a pretty cool way to note that you're using a procedure only for its side effects.

[iimblack]

I'm not arguing either way, just noting that it's counter to what I've seen recently in other languages.