The string indexing extensions are just terrible. There are good reasons why Swift does not provide these things out of the box even though objective-c did: <a href="http:&#x2F;&#x2F;oleb.net&#x2F;blog&#x2F;2014&#x2F;07&#x2F;swift-strings&#x2F;#character-indices-and-ranges" rel="nofollow">http:&#x2F;&#x2F;oleb.net&#x2F;blog&#x2F;2014&#x2F;07&#x2F;swift-strings&#x2F;#character-indice...</a>