Question

Using the standard Django templating system, is there any snippet/reusable template tag to have the first n words in a piece of text wrapped in a tag so I can style them?

What I’m ideally looking for:

{{item.description|wrap:"3 span big"}}

which outputs:

<span class="big">Lorem ipsum dolor</span> sit amet, consectetur adipiscing elit.

If this would be, for any reason, not feasible or really difficult to obtain, I can use JavaScript and do it client side, but I’d like more to be able to do it on page output.

Answer 1

It turns out that writing a filter is really easy (and works exactly the intended way).
This could be made a lot safer, but does the job (and won’t break unless someone passes html as parameters):

from django import template
from django.template.defaultfilters import stringfilter
from django.utils.safestring import mark_safe

register = template.Library()

@register.filter(name='wrap')
@stringfilter
def wrap(value, arg):
    params = arg.split()
    n = int(params[0])
    tag = params[1]
    tagclass = params[2]
    words = value.split()
    head = ' '.join( words[:n] )
    tail = ' '.join( words[n:] )
    return mark_safe('<%s class="%s">%s</%s> %s' % (tag, tagclass, head, tag, tail))