Comment by ralferoo
2 days ago
Well, arguably if it's immutable, then it's not a variable so "var" doesn't make sense. The corollary is if it's a variable it should be mutable so "var mut" is a tautology.
I think "const x = something();" would be logical but they've used const already for compile-time constants. There's probably a sensible way of overloading that use though, depending if the expression would be constant at compile-time or not, but I've not considered it enough to think about edge cases (as it basically reduces to the halting problem unless any functions called are also explicitly marked up as compile time or not).
Trying to pick a good name for the keyword is valid but it's bikeshedding. Either way the keywords should be consistent and a config option is more trouble than it's worth.
And "variables" in math are almost always immutable within a single invocation. It's not a particularly bad word to use. But there's plenty of options. const/var. let/var. let/mut. var/mut I guess. let/set from a sibling comment.