title: Checking if a value exists in an array of structs within a struct
body: <p>Supposing I have two structs. StructA, and StructB which contains an array of StructA's. How am I able to loop through a StructB and check the value of a variable in the StructA's within it?</p>
  
  <pre><code>type StructA struct {
      varA string
      varB string
      varC string
  }    
  
  
  type StructB struct {
      foo  []StructA
  }
  </code></pre>