title: Check if a string is X or is not X
body: <p>I can check if a string equals to a given keyword with regular expressions. Here is an example:</p>
  
  <pre><code>Regex: /^hello$/
  String: hello
  Result: matches, as expected
  
  Regex: /^goodbye$/
  String: goodbye
  Result: matches, as expected
  
  Regex: /^bye$/
  String: bye bye
  Result: does not match, as expected
  </code></pre>
  
  <p>What I can't achieve is to check if a string is not equal to a keyword. Here are some examples of what I am trying to do:</p>
  
  <pre><code>Regex: ^(?!hello).*$
  String: bye
  Result: matches, as expected
  
  Regex: ^(?!hello).*$
  String: bye bye
  Result: matches, as expected
  
  Regex: ^(?!hello).*$
  String: say hello
  Result: matches, as expected
  
  Regex: ^(?!hello).*$
  String: hello you
  Result: does not match, but should match because "hello you" is not equal to "hello"
  </code></pre>
  
  <p>I think I am close with <code>^(?!hello).*$</code> but need a hand on this. Here is another example:</p>
  
  <pre><code>Regex: ^(?!fresh\sfruits).*$
  String: fresh fruits
  Result: does not match, as expected
  
  Regex: ^(?!fresh\sfruits).*$
  String: lots of fresh fruits
  Result: matches, as expected
  
  Regex: ^(?!fresh\sfruits).*$
  String: fresh fruits, love them.
  Result: does not match, but should match
  </code></pre>
  
  <p>Thanks!</p>