xcode has a thing that converts objc to swift. but only kinda. i cannot apparently for example select an fragment of text that is an objc method signature and convert it. so i end up having to do lots of manual utterly annoying ascii boilerplate work and it trains me that xcode and tools are not actually really ever going to come to my aid.
additionally there have been many times where the swift syntax is too opaque to me and so instead of spending 30+ minutes trying to figure it out i end up just brute forcing the code in the stupedist most straight forward way possible like trying to avoid any extensions or protocols or inference or really any bloody subtlety or flexibility of any kind at all.
AAANNDDD they kept on changing the names and signatures so it is hard to know what the right names or syntax even is any more when trying to quickly learn from examples online.
frankly if "read and internalize the entire language spec" is the only way to become successfully facile then the language kinda sucks.
(and yes when i use haskell or s/ml-nj or ocaml i had similar issues so it is a general advanced programming language ui ux thing that people keep doing less than well. but i believe swift has gone far past those in terms of pain and frustration.)
i do not think swift has the best ergonomics.