Re: [htmltmpl] enhancements to H::T

[Mathew R. <mat...@re...>]

> > > - dot syntax, eg 'user.name'
> >
> >Allowing dots in variable names seems harmless enough.
> <snip>
>=20
>=20
> The thing is, 'user.name' isn't a variable name in the traditional=20
> way.  Rather, it's saying 'I want the attribute "name" for the =
variable=20
> "user"', thus providing a more OO approach.
>=20
> I imagine that this would be implemented by passing an object that =
provides=20
> accessors for the fields that would show up in the template.  For the=20
> example above:
>=20
> package My::UserVar;
> use base 'HTML::Template::Var';  # For example
>=20
> sub new
> {
>      my $class =3D shift;
>      my $in =3D shift || { };
>      return unless ref($in) eq 'HASH';
>      my $self =3D { map { $_ =3D> $in->{$_} || '' } qw( name addr city =
state=20
> postal )};
>      bless $self, $class;
> }
> sub name { $_->{name} }
> sub addr   { $_->{addr} }
> sub city    { $_->{city} }
> sub state  { $_->{state} }
> sub postal { $_->{postal} }
>=20
>=20
> package main;
>=20
> # $tmpl defined elsewhere, holding an HTML::Template object
> my $user =3D My::UserVar->new({ name =3D> 'foo', addr =3D> 'bar' });
> $tmpl->param( user =3D> $user );

I hadn't considered doing it this way, though the idea of using a OO =
styled notation appeals to me.  I was thinking along the lines of:


In a template you may do something like:

<TMPL_IF user>
    <TMPL_IF user.name>
       <TMPL_VAR user.name.first> <TMPL_VAR user.name.last>
    </TMPL_IF>
    <TMPL_IF user.address>
        <TMPL_VAR user.address.street>
        <TMPL_VAR user.address.town>
    </TMPL_IF>
</TMPL_IF>


Normally your code would look something like:

if (length $user->name->first or $user->name->last ) {
   $tmpl->param ('user' =3D> 1);
   $tmpl->param ('user.name' =3D> 1);
   $tmpl->param ('user.name.first' =3D> $user->name->first );
   $tmpl->param ('user.name.last' =3D> $user->name->last );
}
if (length $user->address->street or $user->address->town) {
   $tmpl->param ('user' =3D> 1);
   $tmpl->param ('user.address' =3D> 1);
   $tmpl->param ('user.address.street' =3D> $user->address->street);
   $tmpl->param ('user.address.town' =3D> $user->address->town);
}


With the 'structure_vars' support you can do this:

$tmpl->param( 'user.name.first' =3D $user->name->first );
$tmpl->param( 'user.name.last' =3D $user->name->last );
$tmpl->param( 'user.address.street' =3D $user->address->street );
$tmpl->param( 'user.address.town' =3D $user->address->town );

regards,
Mathew