> perl -we' use strict; use warnings; use P; my $tgt_RE1 = qr{ ([SK]) ([0-9]{1-3}) ([-_\.\w]+) }x; my $tgt_RE2 = qr{ ([SK]) ([0-9]{2}) ([-_\.\w]+) }x; my $pat="S01boot.usr-mount"; my @tstAr1 = $pat =~ /$tgt_RE1/; my @tstAr2 = $pat =~ /$tgt_RE2/; P "tstar1=%s", \@tstAr1; P "tstar2=%s", \@tstAr2;' tstar1=[] tstar2=['S', 01, "boot.usr-mount"]