title: Concatenate two dictionaries in Swift
body: <p>Swift gives us plenty new abilities like (at last!) concatenating strings and even arrays. But no support for dictionaries. Is the only way to concatenate dictionaries is to overload + operation for them?</p>
  
  <pre><code>let string = "Hello" + "World" // "HelloWorld"
  let array = ["Hello"] + ["World"] // ["Hello", "World"]
  let dict = ["1" : "Hello"] + ["2" : "World"] // error =(
  </code></pre>