$ perl -e "use Path::Tiny; print path( q{ro/sham/bo} )->basename "

$ perl -Mre=debug -e " $_ = q{ro/sham/bo} ; print m{/([^/]+?)$} "
Compiling REx "/([^/]+?)$"
Final program:
   1: EXACT </> (3)
   3: OPEN1 (5)
   5:   MINMOD (6)
   6:   PLUS (18)
   7:     ANYOF[\x00-.0-\xff][{unicode_all}] (0)
  18: CLOSE1 (20)
  20: EOL (21)
  21: END (0)
anchored "/" at 0 floating ""$ at 2..2147483647 (checking anchored) minlen 2
Guessing start of match in sv for REx "/([^/]+?)$" against "ro/sham/bo"
Found anchored substr "/" at offset 2...
Found floating substr ""$ at offset 10...
Starting position does not contradict /^/m...
Guessed: match at offset 2
Matching REx "/([^/]+?)$" against "/sham/bo"
   2 <ro> </sham/bo>         |  1:EXACT </>(3)
   3 <ro/> <sham/bo>         |  3:OPEN1(5)
   3 <ro/> <sham/bo>         |  5:MINMOD(6)
   3 <ro/> <sham/bo>         |  6:PLUS(18)
                                  ANYOF[\x00-.0-\xff][{unicode_all}] can match 1 times out of 1...
   4 <ro/s> <ham/bo>         | 18:  CLOSE1(20)
   4 <ro/s> <ham/bo>         | 20:  EOL(21)
                                    failed...
                                  ANYOF[\x00-.0-\xff][{unicode_all}] can match 1 times out of 1...
   5 <ro/sh> <am/bo>         | 18:  CLOSE1(20)
   5 <ro/sh> <am/bo>         | 20:  EOL(21)
                                    failed...
                                  ANYOF[\x00-.0-\xff][{unicode_all}] can match 1 times out of 1...
   6 <ro/sha> <m/bo>         | 18:  CLOSE1(20)
   6 <ro/sha> <m/bo>         | 20:  EOL(21)
                                    failed...
                                  ANYOF[\x00-.0-\xff][{unicode_all}] can match 1 times out of 1...
   7 <ro/sham> </bo>         | 18:  CLOSE1(20)
   7 <ro/sham> </bo>         | 20:  EOL(21)
                                    failed...
                                  ANYOF[\x00-.0-\xff][{unicode_all}] can match 0 times out of 1...
                                  failed...
   7 <ro/sham> </bo>         |  1:EXACT </>(3)
   8 <ro/sham/> <bo>         |  3:OPEN1(5)
   8 <ro/sham/> <bo>         |  5:MINMOD(6)
   8 <ro/sham/> <bo>         |  6:PLUS(18)
                                  ANYOF[\x00-.0-\xff][{unicode_all}] can match 1 times out of 1...
   9 <ro/sham/b> <o>         | 18:  CLOSE1(20)
   9 <ro/sham/b> <o>         | 20:  EOL(21)
                                    failed...
                                  ANYOF[\x00-.0-\xff][{unicode_all}] can match 1 times out of 1...
  10 <ro/sham/bo> <>         | 18:  CLOSE1(20)
  10 <ro/sham/bo> <>         | 20:  EOL(21)
  10 <ro/sham/bo> <>         | 21:  END(0)
Match successful!
boFreeing REx: "/([^/]+?)$"

$