Mail::Thread::Chronological - rearrange Mail::Thread::Containers into a Chronological structure


 use Mail::Thread;
 use Mail::Thread::Chronological;

 my $threader = Mail::Thread->new( @messages );
 my $lurker = Mail::Thread::Chronological->new;


 for my $thread ($threader->rootset) {
     for my $row ( $lurker->arrange( $thread ) ) {
         my $container = grep { ref $_ } @$row;
         print join('', map { ref $_ ? '*' : $_ } @$row),
               "    ", $container->messageid, "\n";


Given a Mail::Thread::Container, Mail::Thread::Chronological transforms the tree structure into a 2-dimensional array representing the history of a given thread in time.

The output is similar to that of the Lurker mail archiving system, with a couple of small exceptions:

Characters used

The grid is populated with the characters ' ' (space), '-', '+', '|', '{', or Mail::Thread::Container objects. Lurker uses [a-g], and differentiates T-junctions from corners for you, this module assumes you will do that for yourself.

The characters mean:


empty cell


horizontal line


T junction or corner


vertical line


vertical line crossing over a horizontal line

Vertical stream crossing is permitted

In the original lurker crossing a path vertically is not allowed, this results in a lot of horizontal space being used.



your common or garden constructor


Returns an array of arrays representing the thread tree.

extract_time( $container )

Extracts the time from a Mail::Thread::Container, returned as epoch seconds used to decide the order of adding messages to the rows.


Richard Clamp <>


Lurker, the application that seems to have originated this form of time-based thread display.

Mail::Thread, Mariachi