#!/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")