{ my $actionFlag = 'NONE'; my $Options = build_options(\$actionFlag); my $stack = [[ 'Options', $Options ]]; while ($actionFlag ne 'EXIT') { ... pop @$stack if @$stack > 1; ... Display_Options_and_Get_Response($stack); } } sub Display_Options_and_Get_Response { my $stack = shift; my ($header, $opt) = @{$stack->[-1]}[0, 1]; ... push @$stack, [ ... ]; ... } sub build_options { my $action_flag_ref = shift; return [ ... sub { ... $$action_flag_ref = 'EXIT' } ... ]; }