public static T?TryParseColumn <T>(this ICsvLine csvLine, String columnName, TryParseDelegate <T> tryParse) where T : struct =>
 !csvLine.HasColumn(columnName) ? null : csvLine[columnName]?.TryParse(tryParse);
 public static T?TryParseColumn <T>(this ICsvLine csvLine, String columnName, Func <String, T> parse) where T : struct =>
 !csvLine.HasColumn(columnName) ? null : csvLine[columnName]?.TryParse(parse);