extra_context argument on TemplateView.as_view

[Jeremy]

It used to be possible to pass extra_context to direct_to_template. Then direct_to_template was replaced with TemplateView.as_view ... but the latter function never got the ability to take an extra_context arg.

As a result there are now half a trillion (rough estimate) re-implementations of the following:

class StaticPageView(TemplateView):
    context = None

    def get_context_data(self, **kwargs):
        context = super(StaticPageView, self).get_context_data(**kwargs)
        context.update(self.context or {})
        return context

You can find them across the web, across StackOverflow, etc. Everyone has to remake this one small class just so that they can pass an extra context to template-only views.

This is counter-productive: the whole point of a framework is to *prevent* everyone from having to re-invent the same code. Adding yet another re-implementation of StaticPageView does nothing to improve the code, it only clutters it up with boilerplate.

Please fix this by allowing as_view (ideally in all generic views) to take an extra_context arg.