On Tue, Aug 25, 2009 at 9:26 PM, stevedegrace<degr...@gmail.com> wrote: > I suppose this is easy enough to fix by doing the binding in the view > when the context is first constructed which would probably have been > easier in the first place, but now I'm curious and want to know what's > happening.
If you want something available in the template, then yes, making it available through the context provided in the view is the way to do it. The various built-in template tags which can add variables to the context all have limited scope, and in many cases (e.g., the "with" tag) this is explicit. > I never suspected this behaviour and got no inkling to expect it from > the Django docs. Can anyone with more knowledge of the guts of the > template rendering system suggest why this happens and if there is any > way to force variables bound by custom tags into the "global scope"? The answer is that the template context is not a dictionary. It's a stack of dictionaries, with fall-through lookup semantics. Various operations going on in the template push a new dictionary onto the context stack and populate it, then pop that dictionary off the context stack when they're done. In general, this is a good thing; for example, it means it's much easier to have tags do whatever they want without trampling all over each other's context variables. Many built-in tags take good advantage of this. If you truly need a way to make a variable available everywhere in a template, but it's simply not possible to provide that directly through the initial context, you want to look at the "dicts" attribute of the Context instance, which is a list of dictionaries. The last one in the list (e.g., index -1) is the one that originally came from instantiating the Context with its initial set of variables, and during normal template use it will always persist for the life of the rendering process (someone who wanted to shoot themselves in the foot could write a tag which manually removes it, but the normal context push/pop operations will not do this and will raise an exception if you try to pop the last dictionary out of the stack). -- "Bureaucrat Conrad, you are technically correct -- the best kind of correct." --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com To unsubscribe from this group, send email to django-users+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~----------~----~----~----~------~----~------~--~---
