>perl -wMstrict -lE
"for my $s qw(a b c d) {
   given ($s) {
     when ('a')    { say 'a';  continue;  }
     when ('b')    { say 'b';  continue;  }
     when (/[ab]/) { say ' after a or b'; }
     say 'neither a nor b';
     when ('d')    { say 'd';             }
     default       { say qq{other: '$_'}; }
     }
   }
"
a
 after a or b
b
 after a or b
neither a nor b
other: 'c'
neither a nor b
d