{} is an empty hash reference. I could have started with an empty hash, which might have been a little easier to understand, and I should have annotated my code. So I'll do that here:
# Read in my list of paths and cut off the newlines
my @list_of_paths = <DATA>;
chomp @list_of_paths;
my %hashed_path = ();
for my $path_string (@list_of_paths) {
# This tracks our descent in the path tree. We start at the top
my $hpref = \%hashed_path;
# Split the path into its component directories, and walk through th
+em
for my $dir (split m:/:, $path_string) {
# At each level, if we've never been there before, create an entry
+ for it
$hpref->{$dir} = {} unless exists $hpref->{$dir};
# Then descend into it so we're ready to insert the next level
$hpref = $hpref->{$dir};
}
}
# See what the structure looks like
use Data::Dumper;
print Dumper \%hashed_path;
__DATA__
/top/middle/bottom
/top/middle/newleaf
/top/new_middle/bottom
Output is
$VAR1 = {
'' => {
'top' => {
'middle' => {
'newleaf' => {},
'bottom' => {}
},
'new_middle' => {
'bottom' => {}
}
}
}
};
The topmost level has only the key of empty string because that's the first value in a split on '/' when the string starts with '/'.
Caution: Contents may have been coded under pressure.
| 