$ perl -Mre=debug -e 'qr/0+|1+/;
Final program:
   1: BRANCH (5)
   2:   PLUS (9)
   3:     EXACT <0> (0)
   5: BRANCH (FAIL)
   6:   PLUS (9)
   7:     EXACT <1> (0)
   9: END (0)
minlen 1 

##</code><code>##

 $ perl -Mre=debug -e 'qr/(0)+|(1)+/'
Compiling REx "(0)+|(1)+"
Final program:
   1: BRANCH (12)
   2:   CURLYN[1] {1,32767} (23)
   4:     NOTHING (6)
   6:     EXACT <0> (0)
  10:   WHILEM (0)
  11:   NOTHING (23)
  12: BRANCH (FAIL)
  13:   CURLYN[2] {1,32767} (23)
  15:     NOTHING (17)
  17:     EXACT <1> (0)
  21:   WHILEM (0)
  22:   NOTHING (23)
  23: END (0)
minlen 1 
Freeing REx: "(0)+|(1)+"