Not exactly complex, but long
\define makeSearchExpression(arr, composer, id, instruments, key, movement, movementType, opus, performers, work, workType,)
[tag[movement]regexp:_mvt-arr.[(?i)$arr$]regexp:_mvt-composer[(?i)$composer$]regexp:_mvt-id[$id$]regexp:_mvt-key[$key$]regexp:_mvt-instruments[(?i)$instruments$]regexp:_mvt-movement[(?i)$movement$]regexp:_mvt-movementType[(?i)$movementType$]regexp:_mvt-op.[(?i)$opus$]regexp:_mvt-performers[(?i)$performers$]regexp:_mvt-work[(?i)$work$]regexp:_mvt-workType[(?i)$workType$]]
\end
It constructs a search expression for searching individual movements of classical music works (ripped CDs) in my music player.
If I recall correctly, it’s been a while, the filter didn’t work when split over multiple lines…