As far as I can see from the TT2 docs, there is no native way to do this:

if (template address exists) {
    include template
} else {
    include other template
}

[download]

or more succinctly:

[% INCLUDE 'my/best/choice' || 'my/other/option' %]

Which seems a great shame, especially as TT croaks when a template component is missing. It would allow all sorts of useful structures, most obviously the chance to default to a generic component if no more specific version is available.

It's quite easy to implement from the outside, provided you still have the template path:

sub template_exists {
    my ($self, $file) = @_;
    my $path = $self->config->template_path;
    return 1 if grep { -e && -f && -r } map { "$_/$file" } @$path;
    return;
}

[download]

But it isn't easy to make that look friendly in the templates, which I don't like (and which generates support work, which I also don't like :)

[% FOREACH thing = collection %]
    [% template = factory.template_exists("list/types/${thing.type}.ht
+ml") ?
        "list/types/${thing.type}.html" : 
        "list/types/default.html" 
    %]
    [% INCLUDE $template %]
[% END %]

[download]

So I mostly confine this to the darker corners of the template hierarchy. I'd like to use it more widely, and I can't be alone in that, which makes me think there's an odd bit of syntax or a clever trick that I've missed, and everything could look nice again. Can anyone advise, please, or suggest another approach?

Thanks,
Will

In reply to testing for the existence of a tt template: better way? by thpfft

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