WriteStringFromPlayground.swift

// known-good. Xcode 8, Swift 3

import XCPlayground

/// writes string s to a file in the playground shared directory and returns its URL
func write(string s:String, toPlaygroundSharedDataDirectoryFileWithName name:String) -> URL?
{
  let dirURL:URL = XCPlaygroundSharedDataDirectoryURL as URL
  let fileURL:URL = dirURL.appendingPathComponent(name)
  let path = fileURL.path
  
  FileManager.default.createFile(atPath: path, contents: nil, attributes: nil)
  guard let handle = FileHandle(forWritingAtPath: path) else { return nil }

  defer { handle.closeFile() }
  
  let data:Data = s.data(using: .utf8)!
  
  handle.write(data)

  return fileURL
}