?repeats the group contents below at most once:
\s*a Unicode whitespace character, repeated any number of times
-the literal - (4510 / 558 / 2D16)
—the literal — (821210 / 200248 / 201416)
–the literal – (821110 / 200238 / 201316)
\s*a Unicode whitespace character, repeated any number of times
\d{4}a Unicode decimal digit, repeated exactly 4 times