django_templater_proof_of_concept.py

#!/usr/bin/env python

from inspect import getouterframes, currentframe
from copy import copy

from django.shortcuts import render_to_response

#def render_to_response(*args, **kw):
#    print args, kw

class Templater(object):
    def __init__(self, **kwargs):
        self.args = kwargs
        self._prev = set()

    def __enter__(self):
        self._prev = set(getouterframes(currentframe())[1][0].f_locals.keys())
        return self

    def __exit__(self, type_, value, traceback):
        current = getouterframes(currentframe())[1][0].f_locals
        newvars = set(current.keys()) - self._prev
        for name in newvars:
            if current[name] is not self:
                self.args[name] = current[name]

    def render_to_response(self, template, context_instance=None, mimetype=None):
        return render_to_response(template, self.args, context_instance, mimetype)

def view(request, arg):
    a = 1
    with Templater(arg=arg) as t:
        b = 2

    # send {'arg': arg, 'b': 2} to template.html
    return t.render_to_response("template.html", context_instance="ctx", mimetype="mime")

django_templater_proof_of_concept_wo_context.py

class Templater(object):
    def __init__(self, **kwargs):
        self._args = kwargs

    def __setattr__(self, name, value):
        if name == "_args":
            return super(Templater, self).__setattr__(name, value)
        self._args[name] = value

    def __getattr__(self, name):
        try:
            return self._args[name]
        except KeyError, ex:
            raise AttributeError("%s instance has no attribute %r" % (self.__class__.__name__, name))

    def render_to_response(self, filename, context_instance=None, mimetype=None):
        return render_to_response(filename, self._args, context_instance, mimetype)


def view(request, arg):
    t = Templater(arg=arg)
    t.object = get_object_or_404(User, username=request.user.username)
    t.arg2 = "foobar"
    # Send {'arg': arg, 'object': <User..>, 'arg2': 'foobar'} to template.html
    return l.render_to_response("template.html", context_instance=RequestContext(request))

Warning: No tests.

Qual deveria ser o comportamento esperado se alguém fizer o seguinte?

t = Templater(arg=arg)
a = 1
with t:
    b = 2

Não seria um comportamento mais óbvio salvar self.prev no _enter()?

Sim... seria... :D

Deixa eu corrigir :D