public static bool TryParseInt64(Utf8Span str, out long val)
 {
     if (!Utf8Parser.TryParseInt64(str, out val, out var consumed) || consumed != str.Length())
     {
         return(false);
     }
     return(true);
 }
 public static long ParseInt64(Utf8Span str)
 {
     if (!Utf8Parser.TryParseInt64(str, out var value, out var consumed))
     {
         throw new FormatException();
     }
     if (consumed != str.Length())
     {
         throw new FormatException();
     }
     return(value);
 }