Delphi Tdictionary inheritance : <p>I try to inherit from Tdictionary and somehow the default comparer is lost. This is what I do in essence:</p>

<pre><code>type
  TinpVar = class
  end;
  TinputVars = class(Tdictionary&lt;string,TinpVar&gt;)
  end;
  TLVRvars = class(TinputVars)
    constructor create;
  end;

 constructor TLVRvars.create;
 begin
   inherited;
 end;

 var LVRvars : TLVRvars;

 begin
   LVRvars:=TLVRvars.create;
</code></pre>

<p>With this construction I get an AV when adding a key/value pair to LVRvars. Eventually I found that this can be prevented by changing the constructor of the inherited class to</p>

<pre><code>constructor TLVRvars.create;
begin
  inherited create;
end;
</code></pre>

<p>I do not understand why I have to do that. Although my problem is solved, I would still like to know.</p>
