type 'MyApp::DateOnly' => as 'DateTime'
    => where {     blessed($_)
               &&  $_->isa('DateTime')
               &&  $_->hour == 0  &&  $_->min == 0  && $_->sec == 0
           };

##</code><code>##

coerce  'Search::DateOnly' => from 'DateTime'
    => via { $_->truncate(to => 'day') };

coerce  'Search::DateOnly' => from 'Str'
    => via
    {
        state $parser = DateTime::Format::Strptime->new(
                         pattern => '%Y/%m/%d');
        $parser->parse_datetime($_);
    };

##</code><code>##

has foo => (
            is       => 'ro',
            isa      => 'Maybe[MyApp::DateOnly]',
            coerce   => 1,
           );