New URL tag for reversing urls with placeholder args/kwargs

[h.a.clifford@…]

It would be incredibly useful if Django supported a placeholder url tag:

usage would be similar to url, but with args/kwargs that don't match the url regex.

E.g: {% urlplaceholder User username='<%username%>' %}, where my url rule only allows a-z usernames.
(Currently, you can't do this).

This isn't a huge change which is why I'm suggesting it (line 325 urlresolves does the regex check after substituting in the values)

Why is this useful? It would allow *easy* generation of javascript templates on the frontend - all the current methods seem to involve reversing the urls with javasacript which is hardly in keeping DRY.

Example:

<script id='UserTemplate' type='jqueryTemplate'>
<a href='{% urlplaceholder User username='<%username%>' %}'>
<img src='{% get_media_url %}/user.png'>
</a>
</script>