range_slicing.ipynb

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     "ename": "TypeError",
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      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-7-b894c267d2e9>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m()\u001b[0m\n\u001b[0;32m      3\u001b[0m \u001b[0mx\u001b[0m \u001b[1;33m=\u001b[0m \u001b[1;33m(\u001b[0m\u001b[0mi\u001b[0m \u001b[1;32mfor\u001b[0m \u001b[0mi\u001b[0m \u001b[1;32min\u001b[0m \u001b[0mrange\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;36m50\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      4\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 5\u001b[1;33m \u001b[0mx\u001b[0m\u001b[1;33m[\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;36m5\u001b[0m\u001b[1;33m]\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m: 'generator' object is not subscriptable"
     ]
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   "source": [
    "## normally, if you slice a generator, you get an error\n",
    "\n",
    "x = (i for i in range(50))\n",
    "\n",
    "x[:5]"
   ]
  },
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   "execution_count": 10,
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     "data": {
      "text/plain": [
       "range(0, 5)"
      ]
     },
     "execution_count": 10,
     "metadata": {},
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   "source": [
    "## range intelligently handles this though by implementing a custom slicing operator\n",
    "\n",
    "x = range(10)\n",
    "x[:5]"
   ]
  }
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