public static Maybe <DateTimeOffset> ParseExactToDateTimeOffset(
     this Maybe <string> source,
     string[] format,
     DateTimeStyles style,
     IFormatProvider provider)
 {
     return(source.FlatMap(x => DateTimeOffsetParser.ParseExact(x, format, style, provider)));
 }
 public static Either <TLeft, DateTimeOffset> ParseToDateTimeOffset <TLeft>(
     this Either <TLeft, string> source,
     string[] format,
     DateTimeStyles style,
     IFormatProvider provider,
     TLeft left)
 {
     return(source.FlatMap(x => DateTimeOffsetParser.ParseExact(x, format, style, provider, left)));
 }