\ban ASCII word boundary
httpthe literal text http (case sensitive) s?optionally matches the literal s (11510 / 1638 / 7316) (case sensitive)
\S*any non-whitespace character, repeated any number of times
Non-Capturing Group(?:700[0-9][0-9]{7}|81[0-9][0-9][0-9]{5}|9999[0-9]{8}) 1st Alternative700[0-9][0-9]{7} 0-9one character from 0 (4810) to 9 (5710)
{7}matches exactly 7 characters from the set below:
0-9one character from 0 (4810) to 9 (5710)
2nd Alternative81[0-9][0-9][0-9]{5} 0-9one character from 0 (4810) to 9 (5710)
0-9one character from 0 (4810) to 9 (5710)
{5}matches exactly 5 characters from the set below:
0-9one character from 0 (4810) to 9 (5710)
3rd Alternative9999[0-9]{8} 9999the literal text 9999 {8}matches exactly 8 characters from the set below:
0-9one character from 0 (4810) to 9 (5710)
\ban ASCII word boundary
(*SKIP)acts like (*PRUNE), but the next unanchored match attempt starts where (*SKIP) was reached instead of at the next subject character
(*F)forces the current match attempt to fail at this position