Elixir List Note.ipynb

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       ":c"
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   "source": [
    "Enum.at([:a, :b, :c, :d], 2)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "We cloud write the list [1,2,3] using only such pairs (called cons cells)"
   ]
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       "[1, 2, 3]"
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   "source": [
    "[1 | [2 | [3 | []]]]"
   ]
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   "source": [
    "Some lists, called improper lists, do not have an empty list as the second element in the last cons cell"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Due to their cons cell based representation, prepending an elenment to a list is always fast(constant time), while appending becomes slower as the list grows in size(linear time)"
   ]
  },
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   "cell_type": "code",
   "execution_count": 3,
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     "data": {
      "text/plain": [
       "[1, 2, 3]"
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   ],
   "source": [
    "list = [1,2,3]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[0, 1, 2, 3]"
      ]
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     "execution_count": 6,
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   "source": [
    "[0 | list] #fast"
   ]
  },
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   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[1, 2, 3, 4]"
      ]
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     "execution_count": 8,
     "metadata": {},
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   ],
   "source": [
    "list ++ [4] #slow"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "retrives the last value from history"
   ]
  },
  {
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   "execution_count": 10,
   "metadata": {},
   "outputs": [
    {
     "ename": "FunctionClauseError",
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     "output_type": "error",
     "traceback": [
      "** %FunctionClauseError{args: nil, arity: 2, clauses: nil, function: :nth, kind: nil, module: IEx.History}"
     ]
    }
   ],
   "source": [
    "v"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "prints informatin about the given term"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
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     "text": [
      "\u001b[33mTerm\u001b[0m\n",
      "\u001b[22m  1\u001b[0m\n",
      "\u001b[33mData type\u001b[0m\n",
      "\u001b[22m  Integer\u001b[0m\n",
      "\u001b[33mReference modules\u001b[0m\n",
      "\u001b[22m  Integer\u001b[0m\n",
      "\u001b[33mImplemented protocols\u001b[0m\n",
      "\u001b[22m  Ecto.DataType, Poison.Encoder, Poison.Decoder, IEx.Info, List.Chars, Inspect, String.Chars\u001b[0m\n"
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   ],
   "source": [
    "a = 1\n",
    "i a"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Keyword List"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[a: 1, b: 2]"
      ]
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     "execution_count": 14,
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   ],
   "source": [
    "list = [{:a, 1}, {:b, 2}]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[a: 0, a: 1, b: 2]"
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     "execution_count": 15,
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   ],
   "source": [
    "new_list = [a: 0] ++ list"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Note that values added to the front are the ones fetched on loopup"
   ]
  },
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   "cell_type": "code",
   "execution_count": 17,
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       "0"
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     "execution_count": 17,
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   ],
   "source": [
    "new_list[:a]"
   ]
  },
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   "cell_type": "code",
   "execution_count": 18,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
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     "text": [
      "\u001b[33mTerm\u001b[0m\n",
      "\u001b[22m  {:a, 0}\u001b[0m\n",
      "\u001b[33mData type\u001b[0m\n",
      "\u001b[22m  Tuple\u001b[0m\n",
      "\u001b[33mReference modules\u001b[0m\n",
      "\u001b[22m  Tuple\u001b[0m\n",
      "\u001b[33mImplemented protocols\u001b[0m\n",
      "\u001b[22m  Ecto.Queryable, Ecto.DataType, Poison.Encoder, Poison.Decoder, IEx.Info, Inspect\u001b[0m\n"
     ]
    }
   ],
   "source": [
    "i (List.first new_list)"
   ]
  },
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   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": null,
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