title: Simple compare if an enum is in a list of enums
body: <p>I have the following enum:</p>
  
  <pre><code>public enum Materials { Wood, Stone, Earth, Water, Lava, Air }
  </code></pre>
  
  <p>Now I have 3materials on which i could walk (wood stone earth) and 3 which arent walkable (water lava air)</p>
  
  <p>I would like to make it possible to compare if a flag is one of the three.</p>
  
  <p>At the moment, this is how I do it:</p>
  
  <pre><code>Materials myMat = Materials.Earth;
  if ( myMat == Materials.Earth || myMat == Materials.Wood || myMat == Materials.Stone)
  {
      I can walk on myMat...
  }
  </code></pre>
  
  <p>isnt it possible to create a new flag like Materials.Walkable which would include these three materials so I can just use</p>
  
  <pre><code>if ( myMat == Materials.Walkable )
  </code></pre>
  
  <p>If this is possible, how can I do that?</p>
  
  <p>Thanks in advance ;)</p>