/usr/share/doc/libfile-util-perl/examples/pretty_print_a_directory_using_as_tree.pl is in libfile-util-perl 4.132140-2.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45  | # ABSTRACT: pretty print a directory, recursively, using list_dir( "as_tree" )
# The fool-proof, dead-simple way to pretty-print a directory tree.  Caveat:
# This isn't a method for massive directory traversal, and is subject to the
# limitations inherent in stuffing an entire directory tree into RAM.  Go
# back and use bare callbacks (see other examples) if you need a more efficient,
# streaming (real-time) pretty-printer where top-level sorting is less
# important than resource constraints and speed of execution.
# set this to the name of the directory to pretty-print
my $treetrunk = '.';
use warnings;
use strict;
use lib './lib';
use File::Util qw( NL SL );
my $ftl = File::Util->new( { onfail => 'zero' } );
walk( $ftl->list_dir( $treetrunk => { as_tree => 1, recurse => 1 } ) );
exit;
sub walk
{
   my ( $branch, $depth ) = @_;
   $depth ||= 0;
   talk( $depth - 1, $branch->{_DIR_SELF_} . SL ) if $branch->{_DIR_SELF_};
   delete @$branch{ qw( _DIR_SELF_  _DIR_PARENT_ ) };
   talk( $depth, $branch->{ $_ } ) for sort { uc $a cmp uc $b } keys %$branch;
}
sub talk
{
   my ( $indent, $item ) = @_;
   return walk( $item, $indent + 1 ) if ref $item;
   print(  ( ' ' x ( $indent * 3 ) ) . ( $item || '' ) . NL );
}
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