Well, set idea was just a small proposal, which had to help me in solving a harder problem. I wanted to add something like extensionable literal. The idea is that when compiler sees some special literal, it reads it, turns into an object and sends #parse message to it. After that literal answers something which compiler uses and considers as a result of this literal. Example:
`#{1 2 3}`
So compiler sees that literal initializes with it and object. Then object receives #parse message. It easily defines that its contents is set ctration and after parsing returns set object. This idea is my original intention. I hope its better than previous.