use Data::Processor;
my $schema = {
  section => {
      description => 'a section with a few members',
      error_msg   => 'cannot find "section" in config',
      members => {
          foo => {
              # value restriction either with a regex..
              value => qr{f.*},
              description => 'a string beginning with "f"'
          },
          bar => {
              # ..or with a validator callback.
              validator => sub {
                  my $self   = shift;
                  my $parent = shift;
                  # undef is "no-error" -> success.
                  no strict 'refs';
                  return undef
                      if $self->{value} == 42;
              }
          },
          wuu => {
              optional => 1
          }
      }
  }
};

my $p = Data::Processor->new($schema);

my $data = {
  section => {
      foo => 'frobnicate',
      bar => 42,
      # "wuu" being optional, can be omitted..
  }
};

my $error_collection = $p->validate($data, verbose=>0);
# no errors :-)

# in case of errors:
# ------------------
# print each error on one line.
say $error_collection;

# same
for my $e ($error_collection->as_array){
    say $e;
    # do more..
}

my $processor = Data::Processor->new($schema);

my $error_collection = $processor->validate($data, verbose=>0);

my $error_collection = $processor->validate_schema();

my $error_collection = $processor->merge_schema($schema_2);

my $validator = Data::Processor::Validator->new($schema, data => $data)
my $error_string = $processor->transform($key, $schema_key, $value);

my $data = $processor->make_data(data=>$data);

my $pod_string = $processor->make_pod();