How to capture multiple repeated groups?

Question

I need to capture multiple groups of the same pattern. Suppose, I have a following string:

HELLO,THERE,WORLD

And I\'ve written a following

Answer 1

Sorry, not Swift, just a proof of concept in the closest language at hand.

// JavaScript POC. Output:
// Matches:  ["GOODBYE","CRUEL","WORLD","IM","LEAVING","U","TODAY"]

let str = `GOODBYE,CRUEL,WORLD,IM,LEAVING,U,TODAY`
let matches = [];

function recurse(str, matches) {
    let regex = /^((,?([A-Z]+))+)$/gm
    let m
    while ((m = regex.exec(str)) !== null) {
        matches.unshift(m[3])
        return str.replace(m[2], '')
    }
    return "bzzt!"
}

while ((str = recurse(str, matches)) != "bzzt!") ;
console.log("Matches: ", JSON.stringify(matches))

Note: If you were really going to use this, you would use the position of the match as given by the regex match function, not a string replace.