\(?optionally matches the literal ( (4010 / 508 / 2816)
0-8one character from 0 (4810) to 8 (5610)
Character Class[2-8]{0,1} {0,1}matches at most one character from the set below:
2-8one character from 2 (5010) to 8 (5610)
\)?optionally matches the literal ) (4110 / 518 / 2916)
\s*any whitespace character, repeated any number of times
?matches at most one character from the set below:
\Dany character that's not a digit
\s*any whitespace character, repeated any number of times
{4}matches exactly 4 characters from the set below:
0-9one character from 0 (4810) to 9 (5710)
\s*any whitespace character, repeated any number of times
?matches at most one character from the set below:
\Dany character that's not a digit
\s*any whitespace character, repeated any number of times
{4}matches exactly 4 characters from the set below:
0-9one character from 0 (4810) to 9 (5710)