^start of line
.*?any character (except for line terminators), repeated any number of times
\/the literal / (4710 / 578 / 2F16)
Group mnemonic(?<mnemonic>.{2,8}?) .{2,8}?any character (except for line terminators), repeated between 2 and 8 times
_the literal _ (9510 / 1378 / 5F16)
Group isbn(?<isbn>\d{13}) \d{13}a digit, repeated exactly 13 times
_the literal _ (9510 / 1378 / 5F16)
Group primaryId(?<primaryId>.+?) .+?any character (except for line terminators), repeated at least once
_the literal _ (9510 / 1378 / 5F16)
Group secondaryId(?<secondaryId>tcx\d{0,3}) tcxthe literal text tcx (case sensitive) \d{0,3}a digit, repeated between 0 and 3 times
Non-Capturing Group(?:_r(?<revisionNumber>\d+))? ?repeats the group contents below at most once:
_rthe literal text _r (case sensitive) Group revisionNumber(?<revisionNumber>\d+) \d+a digit, repeated at least once
\.the literal . (4610 / 568 / 2E16)
Group extension(?<extension>indd|qxp|qxd) inddthe literal text indd (case sensitive) qxpthe literal text qxp (case sensitive) qxdthe literal text qxd (case sensitive) $end of line
g modifier: global. Finds all matches instead of stopping after the first
m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string