Next The Identity Function 32

Directory Searching

 sub walk_tree {
 my ($dir, $filefunc, $dirfunc) = @_;
 if (-d $dir) {
 $dirfunc->($dir);
 opendir my $dh, $dir or return;
 while (my $file = readdir $dh) {
 next if $file eq '.' || $file eq '..';
 walk_tree("$dir/$file", $filefunc, $dirfunc);
 }
 } else {
 $filefunc->($dir);
 }
 }

Now we can print just the names of the directories:

 walk_tree($DIR, sub {}, sub { print $_[0] });

Or accumulate a list of plain files:

 my @FILES;
 walk_tree($DIR, sub {push @FILES, $_[0]}, sub {});