use HTML::ValidationRules;
my $parser = HTML::ValidationRules->new;
my $rules = $parser->load_rules(file => 'form.html');
# rules will be extracted as follows:
# [
# text => [ [ HTML_PATTERN => '[A-Za-z0-9]+' ],
[ HTML_MAXLENGTH => 255 ] ],
# url => [ HTML_URL => [ HTML_MAXLENGTH =>
255 ], 'NOT_BLANK' ],
# email => [ HTML_EMAIL => [ HTML_MAXLENGTH =>
255 ], 'NOT_BLANK' ],
# number => [ HTML_NUMBER => [ HTML_MIN => 200 ],
[ HTML_MAX => 800 ] ],
# textarea => [ [ HTML_MAXLENGTH => 1000 ],
'NOT_BLANK' ],
# range => [ HTML_RANGE => [ HTML_MIN => 20 ],
[ HTML_MAX => 80 ] ],
# ]