Question

I’m developing a project on Google AppEngine, using Django templates, so I have to use tags like {{ aitem.Author }} to print content within my HTML template.

Author, however, can either be a string or a list object, and I have no way to tell it in advance. When the Author is a list and I try to print it on my template, I get the ugly result of

Author: [u’J. K. Rowling’, u’Mary GrandPr\xe9′]

Is there any way to handle this kind of scenario (basically printing a field differently depending on its type) effectively? Do I have to rely on custom tags or any other means?

Answer 1

I think the cleanest solution would be to add a method to the model get_authors() which always returns a list either of one or more authors. Then you can use:

Author: {{ aitem.get_authors|join:", " }}

If you for some reason have only access to the templates and can’t change the model, then you can use a hack like this:

{% if "[" == aitem.Author|pprint|slice:":1" %}
    Author: {{ aitem.Author|join:", " }}
{% else %}
    Author: {{ aitem.Author }}
{% endif %}

P.S. it’s not a good convention to use capital letters for attribute names.