216 Code flow: 1: main::three 2: main::two 3: main::_helper 4: main::one 5: main::calc 6: main::display Stack trace: in: main::three sub: - file: test.pl line: 7 package: main in: main::two sub: main::three file: test.pl line: 13 package: main in: main::_helper sub: main::two file: test.pl line: 17 package: main in: main::one sub: main::two file: test.pl line: 17 package: main in: main::calc sub: main::one file: test.pl line: 21 package: main in: main::display sub: main::one file: test.pl line: 22 package: main