title: No matching function for call to object of type 'const RadioMap::comp'
body: <pre><code>struct comp
  {
      bool operator()(const CartesianLocation&amp; loc1, const CartesianLocation&amp; loc2)
      {
          //Compare the 2 locations, return true if loc1 is less than loc2
          return loc1.id &lt; loc2.id;
      }
  };
  
  std::map&lt;CartesianLocation, std::list&lt;RadioSignal&lt;RadioDevice&gt;&gt;, comp&gt; radioMap;
  
  public:
    void add(CartesianLocation location, std::list&lt;RadioSignal&lt;RadioDevice&gt;&gt; observedSignals) {
      radioMap[location] = observedSignals;
    }
  </code></pre>
  
  <p>On this line <code>radioMap[location] = observedSignals;</code> I am getting below error:</p>
  
  <blockquote>
    <p>No matching function for call to object of type 'const RadioMap::comp' on this line if (__tree_.value_comp().key_comp()(__k, __nd->__value_.__cc.first))</p>
  </blockquote>
  
  <p>Any idea where I may be wrong?</p>