public ParameterDataProvider(Document document, ProjectInformation info, string functionName)
        {
            this.document     = document;
            this.functionName = functionName;

            functions = new List <Symbol> ();
            Symbol function = info.GetFunction(functionName, document.FileName, document.Editor.Caret.Line + 1, document.Editor.Caret.Column + 1);

            if (null != function)
            {
                functions.Add(function);
            }
        }        // member function constructor
        public ParameterDataProvider(Document document, ProjectInformation info, string functionName)
        {
            this.editor       = document.TextEditor;
            this.functionName = functionName;
            this.info         = info;

            functions = new List <Symbol> ();
            Symbol function = info.GetFunction(functionName, document.FileName, editor.CursorLine, editor.CursorColumn);

            if (null != function)
            {
                functions.Add(function);
            }
        }        // member function constructor