ContainsMatcher.swift

import Foundation


struct Contains {
  let value: String
  init(_ str: String) {
    value = str
  }
}


func ~=(pattern: Contains, value: String) -> Bool{
  return value.contains(pattern.value)
}


switch "hello" {
case Contains("ll"):
  print("match")
default:
  print("none")
}

nice!

i likey! i would change your struct to just clean it up though

struct Contains { let value: String }

Sure! And YMMV. But if we did that, then we'd have to write case Contains(value: "ll") which feels too wordy to me.