{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": [
    "from inspect import stack"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 27,
   "metadata": {},
   "outputs": [],
   "source": [
    "def fstring(s, **kwargs):\n",
    "    caller = stack()[1][0]\n",
    "    ns = caller.f_globals.copy()\n",
    "    ns.update(caller.f_locals)\n",
    "    caller.f_locals['q'] = 6\n",
    "    print(caller.f_locals)\n",
    "    ns.update(kwargs)\n",
    "    return s.format(**ns)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 28,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": [
    "class Animal:\n",
    "    name = 'bob'"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 29,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": [
    "y = 7\n",
    "\n",
    "def caller():\n",
    "    x = 5\n",
    "    bob = Animal\n",
    "    s = fstring('His name is {bob.name}, {x:06x}, {y}, {z}', z=9)\n",
    "    print(s)\n",
    "    \n",
    "    # The following does not work in Python 3.0 because the\n",
    "    # list comprehension runs with its own local namespace.\n",
    "    #t = [fstring('{i} {x} {y} {z}', z=11) for i in range(4)]\n",
    "    #print(t)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 30,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{'bob': <class '__main__.Animal'>, 'x': 5, 'q': 6}\n",
      "His name is bob, 000005, 7, 9\n"
     ]
    }
   ],
   "source": [
    "caller()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 25,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{'i': 0, '.0': <range_iterator object at 0x7ffb2c5da750>}\n",
      "{'i': 1, '.0': <range_iterator object at 0x7ffb2c5da750>}\n",
      "{'i': 2, '.0': <range_iterator object at 0x7ffb2c5da750>}\n",
      "{'i': 3, '.0': <range_iterator object at 0x7ffb2c5da750>}\n"
     ]
    },
    {
     "data": {
      "text/plain": [
       "['0 4 7 11', '1 4 7 11', '2 4 7 11', '3 4 7 11']"
      ]
     },
     "execution_count": 25,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "[fstring('{i} {x} {y} {z}', x=4, z=11) for i in range(4)]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 26,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "False"
      ]
     },
     "execution_count": 26,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "'x' in globals()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": []
  }
 ],
 "metadata": {
  "kernelspec": {
   "display_name": "Python 3",
   "language": "python",
   "name": "python3"
  },
  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 3
   },
   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython3",
   "version": "3.6.1"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 2
}