DB<173> p $_ = join " ", map { "$_" x 3 } qw/. a b C a d C e C ./
... aaa bbb CCC aaa ddd CCC eee CCC ...
  DB<174> ; /(aaa.*?CCC)/gc;  $last= $1                    # $1 reset in next debugger line

  DB<175> @res = map { $last .= $_ } ("", /\G(.*?CCC)/g)

  DB<176> x @res
0  'aaa bbb CCC'
1  'aaa bbb CCC aaa ddd CCC'
2  'aaa bbb CCC aaa ddd CCC eee CCC'
  DB<177>