I've encountered in some code the following call :
SQLParser.Parse(qry.SQL.Text)().GetWhereClause 
and I don't understand the meaning of those 2 parenthesis after the Parse call. Following the implementation I got the declarations for each one of them:
 TSQLParser = class
  public
    class function Parse(const ASQL: string): ISmartPointer<TSQLStatement>;
  TSQLStatement = class
    function GetWhereClause: string;
and
  ISmartPointer<T> = reference to function: T;
                The Parse function returns a reference to a function. You can call this function. A longer equivalent form would be:
var
  FunctionReference: ISmartPointer<TSQLStatement>;
  SQLStatement: TSQLStatement;
begin
  { Parse returns a reference to a function. Store that function reference in FunctionReference }
  FunctionReference := TSQLParser.Parse(qry.SQL.Text);
  { The referenced function returns an object. Store that object in SQLStatement }
  SQLStatement := FunctionReference();
  { Call the GetWhereClause method on the stored object }
  SQLStatement.GetWhereClause();
The line in the question is just a shorter version that does not use explicit variables to store the intermediate results.
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