[mckn1ght]

Apple does use Swift in their IDE, Xcode. Several years ago they rewrote the text editor component in Swift. It’s taken them a while to get all the features back that the old one had, and has had a fair amount of bugs as well. I often wonder why they didn’t just leave it in ObjC and add the new features they wanted to add, like the minimap or sticky declaration heaters.

I definitely wouldn’t call Swift a 10x improvement in efficiency, and I like coding in Swift. I do advent of code in it each year, but spend a fair amount of time just fighting with the compiler–after all these years, it still emits strange or just flat out incorrect diagnostics.

[internetter]

I concur. I'm 10k LOC deep into a SwiftUI app (Absolutely no clue how much that works out to be in Objective C + UIKit equivalent code), and one of the most frustrating things (after all the stuff you can't do without a PhD in apple internals) is how piss poor Swift errors are. I've changed a line of code in one file, and then another, completely unrelated one stopped compiling. Most frequently, it's something about how checking the file took too long and it should be broken up (which you will learn, really means you have a small error somewhere in said file and swift isn't in a sharing mood)