📣 Some time ago we have conducted a UX research that showed that Kotlin users may experience troubles identifying whether the ranges created with the

..

operator and

until

function have their upper bound excluded or included. Now we present the proposal intended to improve this situation by introducing the new

..<

(rangeUntil) operator to Kotlin. Please use KEEP-314 for the discussion.

that's exciting. it isn't something i thought about wanting, but now that I see it, I quite like it. nice to see the language evolving. to be clear, would this impyl that ..< would be the new recommendations and

until

would be deprecated or warned on? or just an additional synonym?

We plan to give a recommendation to use

..<

instead of

until

in IDEA without deprecating the latter for the time being

Having very recently spent a bunch of time confusing myself with ranges, this is a very welcome addition!

I'm assuming the first feature requests after

..<

will be

>..

and

>..<

not that I can think of use-cases for them The IntelliJ type hints showing these when using

..

and

until

are already super useful