pretty_OrderedDict.ipynb

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  "signature": "sha256:2ad956e11f831e68c36ab4dfdff6dd1c1e0945200972c9bfe98254641a3c1bea"
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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import json\n",
      "from collections import OrderedDict\n",
      "import numpy as np"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 1
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "class AnyEncoder(json.JSONEncoder):\n",
      "    def default(self, obj):\n",
      "        \"\"\"\n",
      "        This method gets called for any `obj` type that is unsupported by JSON.\n",
      "        In this case just delegate to the object __str__ method, which is\n",
      "        (basically) guaranteed to succeed.\n",
      "        \"\"\"\n",
      "        return str(obj)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 2
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "class PrettyOrderedDict(OrderedDict):\n",
      "    \"\"\"\n",
      "    Use JSON to provide a pretty string representation for OrderedDict.\n",
      "    In this concept the astropy.utils.OrderedDict would be this subclass\n",
      "    and never the \"native\" collections.OrderedDict, even for python >= 2.7.\n",
      "    \"\"\"\n",
      "    def __str__(self):\n",
      "        return json.dumps(self, indent=4, separators=(',', ': '), cls=AnyEncoder)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 3
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "class MyClass:\n",
      "    pass\n",
      "mc = MyClass\n",
      "\n",
      "class MyList(list):\n",
      "    pass\n",
      "ml = MyList\n",
      "\n",
      "class MyDict(dict):\n",
      "    pass\n",
      "md = MyDict(xx=5)\n",
      "\n",
      "mod = PrettyOrderedDict([('bb', 2), ('aa', 1)])\n",
      "\n",
      "ar = np.arange(5)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 4
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "**Define a nested OrderedDict structure and see useless str() output**"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "od = OrderedDict([('z', mc), \n",
      "                  ('y', {'b': ml, \n",
      "                         'a': ar, \n",
      "                         'md': md, \n",
      "                         'mod': mod})])\n",
      "print(od)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "OrderedDict([('z', <class __main__.MyClass at 0x104f7c598>), ('y', {'a': array([0, 1, 2, 3, 4]), 'md': {'xx': 5}, 'b': <class '__main__.MyList'>, 'mod': PrettyOrderedDict([('bb', 2), ('aa', 1)])})])\n"
       ]
      }
     ],
     "prompt_number": 5
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "**Now the nicely formatted version utilizing the JSON encoder**"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "print(PrettyOrderedDict(od))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "{\n",
        "    \"z\": \"__main__.MyClass\",\n",
        "    \"y\": {\n",
        "        \"a\": \"[0 1 2 3 4]\",\n",
        "        \"md\": {\n",
        "            \"xx\": 5\n",
        "        },\n",
        "        \"b\": \"<class '__main__.MyList'>\",\n",
        "        \"mod\": {\n",
        "            \"bb\": 2,\n",
        "            \"aa\": 1\n",
        "        }\n",
        "    }\n",
        "}\n"
       ]
      }
     ],
     "prompt_number": 6
    }
   ],
   "metadata": {}
  }
 ]
}