gistfile1.swift

import Foundation

let content = "abc,cde,5.5,128,256\nefg,ghi,42"

let parsedCSV: [[CustomStringConvertible]] = content
  .components(separatedBy: "\n")
  .map({ // Step 1
    $0.components(separatedBy: ",")
      .map({ // Step 2
        if let int = Int($0) {
          return int
        } else if let double = Double($0) {
          return double
        }
        return $0
      })
  })


print(parsedCSV)
// [["abc", "cde", 5.5, 128, 256], ["efg", "ghi", 42]]

It works as long as there are no commas within a string
"abc", "c, de", 5.5, 128
"efg", "ghi", 13.5, 42

It will fail at the string "c, de"

It will also fail for files which use "\r" or "\r\n" instead of "\n".