diff --git a/notebooks/lark.ipynb b/notebooks/lark.ipynb
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+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": 38,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from lark import Lark, Transformer, v_args\n",
+    "\n",
+    "import re\n",
+    "import sys\n",
+    "\n",
+    "def split_floors(text):     \n",
+    "    return re.split(' to | via ',text)\n",
+    "    \n",
+    "def parse(s):\n",
+    "    floors = split_floors(s)\n",
+    "    rez = []\n",
+    "    err = \"\"\n",
+    "    for floor in floors:\n",
+    "        tree = None\n",
+    "        try:\n",
+    "            tree = l1.parse(floor)\n",
+    "        except:\n",
+    "            err += f\"l1 failed to parse: {floor}\\n{sys.exc_info()}\\n\"\n",
+    "        if tree is None:\n",
+    "            try:\n",
+    "                tree = l2.parse(floor)\n",
+    "            except:    \n",
+    "                err += f\"l2 failed to parse: {floor}\\n{sys.exc_info()}\\n\"\n",
+    "        if tree is None:\n",
+    "            continue\n",
+    "        rez.append(TreeToObj().transform(tree))\n",
+    "    return [platform for sublist in rez for platform in sublist], err"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 42,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "class Platform:\n",
+    "    def __init__(self, lines, direction):\n",
+    "        self.lines = lines\n",
+    "        self.direction = direction if direction else Direction(\"both directions\")\n",
+    "    \n",
+    "    def __str__(self):\n",
+    "        return f\"<dir {self.direction}, lines {self.lines}>\"\n",
+    "    \n",
+    "    def __repr__(self):\n",
+    "        return str(self)\n",
+    "    \n",
+    "class Direction:\n",
+    "    BOTH = [\"north\", \"south\"]\n",
+    "    def __init__(self, direction):\n",
+    "        if \"both directions\" in direction:\n",
+    "            self.direction = self.BOTH\n",
+    "        else:\n",
+    "            self.direction = [re.sub(\"-bound\", \"\", str(direction))]\n",
+    "\n",
+    "    def __str__(self):\n",
+    "        return str(self.direction) \n",
+    "    \n",
+    "    def __repr__(self):\n",
+    "        return self.direction\n",
+    "\n",
+    "class Lines:\n",
+    "    def __init__(self, lines):\n",
+    "        self.lines = [str(line) for line in lines]\n",
+    "        \n",
+    "    def __str__(self):\n",
+    "        return str(self.lines)\n",
+    "    \n",
+    "    def __repr__(self):\n",
+    "        return self.lines "
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 49,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "#(?<=and ).*-(?=bound)\n",
+    "# uptown A/B/C service -> direction line \"service\"\n",
+    "# A/B/C service in both directions -> line \"service\" direction\n",
+    "# uptown 6 and E/M service in both directions\n",
+    "#         | /(\\w+(?<!and) )*\\w+-bound/\n",
+    "\n",
+    "service = r\"\"\"\n",
+    "    services : (service \"and\")* service\n",
+    "        \n",
+    "    service : [floor \"for\"] [lines] \"service in both directions\"\n",
+    "        | [floor \"for\"] direction (directionless_service \"and\")* directionless_service\n",
+    "        \n",
+    "    directionless_service : lines [floor]\n",
+    "        | floor\n",
+    "\"\"\"\n",
+    "\n",
+    "simple_dir = r\"\"\"\n",
+    "    direction : /(uptown|downtown)/i\n",
+    "        | /\\w+-bound/\n",
+    "        | /terminal/i\n",
+    "        | /(\\w+(?<!and) )*\\w+-bound/\n",
+    "\"\"\"\n",
+    "\n",
+    "complex_dir = simple_dir + r\"\"\"\n",
+    "        | /\\w.*-bound/\n",
+    "\"\"\"\n",
+    "\n",
+    "base = r\"\"\"\n",
+    "    floor : \"terminal\"i | \"service\"i | \"platform\"i | \"mezzanine\"i\n",
+    "    \n",
+    "    lines : _line\n",
+    "    \n",
+    "    _line : /([a-zA-Z0-9])/\n",
+    "        | _line \"and\" _line\n",
+    "        | (_line \"/\")* _line\n",
+    "    \n",
+    "    %import common.WS\n",
+    "    %ignore WS\n",
+    "\"\"\"\n",
+    "\n",
+    "l1 = Lark(service + simple_dir + base, start='services')\n",
+    "\n",
+    "l2 = Lark(service + complex_dir + base, start='services')\n",
+    "\n",
+    "@v_args(inline=True)\n",
+    "class TreeToObj(Transformer):    \n",
+    "    direction = lambda self, x: Direction(str(x))\n",
+    "    line = lambda self, x: str(x)\n",
+    "    lines = lambda self, *x: Lines(x)\n",
+    "    directionless_service = lambda self, *x: [i for i in x if isinstance(i, Lines)]\n",
+    "    \n",
+    "    def service(self, *args):\n",
+    "        lines = []\n",
+    "        direction = None\n",
+    "\n",
+    "        for arg in args:\n",
+    "            if isinstance(arg, list):\n",
+    "                for subarg in arg:\n",
+    "                    if isinstance(subarg, Lines):\n",
+    "                        lines.append(subarg)\n",
+    "            elif isinstance(arg, Direction):\n",
+    "                direction = arg\n",
+    "            elif isinstance(arg, Lines):\n",
+    "                lines.append(arg)\n",
+    "        rez = []\n",
+    "        if len(lines):\n",
+    "            for line in lines:\n",
+    "                rez.append(Platform(line, direction))\n",
+    "        else:\n",
+    "            rez.append(Platform(None, direction))\n",
+    "        return rez\n",
+    "    \n",
+    "    def services(self, *x):\n",
+    "        rez = []\n",
+    "        for service in x:\n",
+    "            for platform in service:\n",
+    "                if isinstance(platform, Platform):\n",
+    "                    rez.append(platform)\n",
+    "        return rez\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 51,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "===========\n",
+      "uptown 6 and E/M service in both directions\n",
+      "SUCCESS: [<dir ['uptown'], lines ['6']>, <dir ['north', 'south'], lines ['E', 'M']>]\n",
+      "===========\n",
+      "mezzanine to Manhattan-bound platform\n",
+      "SUCCESS: [<dir ['Manhattan'], lines None>]\n",
+      "===========\n",
+      "mezzanine to Pelham Bay Parkway-bound platform\n",
+      "SUCCESS: [<dir ['Pelham Bay Parkway'], lines None>]\n",
+      "===========\n",
+      "mezzanine to uptown a/b/c service\n",
+      "SUCCESS: [<dir ['uptown'], lines ['a', 'b', 'c']>]\n",
+      "===========\n",
+      "Manhattan-bound Platform via mezzanine\n",
+      "SUCCESS: [<dir ['Manhattan'], lines None>]\n",
+      "===========\n",
+      "mezzanine to service in both directions\n",
+      "SUCCESS: [<dir ['north', 'south'], lines None>]\n",
+      "===========\n",
+      "mezzanine to a/b service in both directions\n",
+      "SUCCESS: [<dir ['north', 'south'], lines ['a', 'b']>]\n",
+      "===========\n",
+      "mezzanine to a/b and 4 service in both directions\n",
+      "SUCCESS: [<dir ['north', 'south'], lines ['a', 'b', '4']>]\n",
+      "===========\n",
+      "mezzanine to terminal platform\n",
+      "SUCCESS: [<dir ['terminal'], lines None>]\n",
+      "===========\n",
+      "downtown 6 platform to underpass for access to uptown 6 and E/M service in both directions\n",
+      "SUCCESS: [<dir ['downtown'], lines ['6']>, <dir ['uptown'], lines ['6']>, <dir ['north', 'south'], lines ['E', 'M']>]\n",
+      "===========\n",
+      "2/3 service in both directions and Manhattan-bound 4 service\n",
+      "SUCCESS: [<dir ['north', 'south'], lines ['2', '3']>, <dir ['Manhattan'], lines ['4']>]\n",
+      "===========\n",
+      "platform for 2/3 service in both directions and test-bound 4 service\n",
+      "SUCCESS: [<dir ['north', 'south'], lines ['2', '3']>, <dir ['test'], lines ['4']>]\n",
+      "===========\n",
+      "mezzanine to platform for Far Rockaway - Mott Av and Rockaway Park - Beach 116 St-bound service\n",
+      "SUCCESS: [<dir ['Far Rockaway - Mott Av and Rockaway Park - Beach 116 St'], lines None>]\n",
+      "===========\n",
+      "25 St & Lexington Ave (NE corner) to mezzanine for service in both directions\n",
+      "SUCCESS: [<dir ['north', 'south'], lines None>]\n",
+      "===========\n",
+      "125 St & St Nicholas Ave (SW corner) to mezzanine for service in both directions\n",
+      "SUCCESS: [<dir ['north', 'south'], lines None>]\n"
+     ]
+    }
+   ],
+   "source": [
+    "class TestCase:\n",
+    "    def __init__(self, case, expected):\n",
+    "        self.case = case\n",
+    "        self.expected = expected\n",
+    "    \n",
+    "    def check(self, actual, err):\n",
+    "        conv_actual = [str(a) for a in actual]\n",
+    "        \n",
+    "        for e in self.expected:\n",
+    "            if str(e) not in conv_actual:\n",
+    "                print(err)\n",
+    "                raise Exception(f\"expected: {e}, to be in {actual}\")\n",
+    "                \n",
+    "        if len(actual) != len(self.expected):\n",
+    "            print(err)\n",
+    "            raise Exception(f\"expected: {self.expected}, actual: {actual}\")\n",
+    "            \n",
+    "        print(f\"SUCCESS: {actual}\")\n",
+    "\n",
+    "def plat(direction=None, lines=None):\n",
+    "    return Platform(\n",
+    "        Lines(lines) if lines else None,\n",
+    "        Direction(direction) if direction else None)\n",
+    "            \n",
+    "tests = [\n",
+    "    TestCase(\n",
+    "        \"uptown 6 and E/M service in both directions\",\n",
+    "        [plat(direction=\"uptown\", lines=[\"6\"]), plat(direction=\"both directions\", lines=[\"E\", \"M\"])]\n",
+    "    ),\n",
+    "    TestCase(\n",
+    "        \"mezzanine to Manhattan-bound platform\",\n",
+    "        [plat(direction=\"Manhattan\")]\n",
+    "    ),\n",
+    "    TestCase(\n",
+    "        \"mezzanine to Pelham Bay Parkway-bound platform\",\n",
+    "        [plat(direction=\"Pelham Bay Parkway\")]\n",
+    "    ),\n",
+    "    TestCase(\n",
+    "        \"mezzanine to uptown a/b/c service\",\n",
+    "        [plat(direction=\"uptown\", lines=[\"a\", \"b\", \"c\"])]\n",
+    "    ),\n",
+    "    TestCase(\n",
+    "        \"Manhattan-bound Platform via mezzanine\",\n",
+    "        [plat(direction=\"Manhattan\")]\n",
+    "    ),\n",
+    "    TestCase(\n",
+    "        \"mezzanine to service in both directions\",\n",
+    "        [plat(direction=\"both directions\")]\n",
+    "    ),\n",
+    "    TestCase(\n",
+    "        \"mezzanine to a/b service in both directions\",\n",
+    "        [plat(direction=\"both directions\", lines=[\"a\", \"b\"])]\n",
+    "    ),\n",
+    "    TestCase(\n",
+    "        \"mezzanine to a/b and 4 service in both directions\",\n",
+    "        [plat(direction=\"both directions\", lines=[\"a\", \"b\", \"4\"])]\n",
+    "    ),\n",
+    "    TestCase(\n",
+    "        \"mezzanine to terminal platform\",\n",
+    "        [plat(direction=\"terminal\")]\n",
+    "    ),\n",
+    "    TestCase(\n",
+    "        \"downtown 6 platform to underpass for access to uptown 6 and E/M service in both directions\",\n",
+    "        [plat(direction=\"downtown\", lines=[\"6\"]), plat(direction=\"uptown\", lines=[\"6\"]), plat(direction=\"both directions\", lines=[\"E\", \"M\"])]\n",
+    "    ),\n",
+    "    TestCase(\n",
+    "        \"2/3 service in both directions and Manhattan-bound 4 service\",\n",
+    "        [plat(direction=\"Manhattan\", lines=[\"4\"]), plat(direction=\"both directions\", lines=[\"2\", \"3\"])]\n",
+    "    ),\n",
+    "    TestCase(\n",
+    "        \"platform for 2/3 service in both directions and test-bound 4 service\",\n",
+    "        [plat(direction=\"test\", lines=[\"4\"]), plat(direction=\"both directions\", lines=[\"2\", \"3\"])]\n",
+    "    ),\n",
+    "    TestCase(\n",
+    "        \"mezzanine to platform for Far Rockaway - Mott Av and Rockaway Park - Beach 116 St-bound service\",\n",
+    "        [plat(direction=\"Far Rockaway - Mott Av and Rockaway Park - Beach 116 St\")]\n",
+    "    ),\n",
+    "    TestCase(\n",
+    "        \"25 St & Lexington Ave (NE corner) to mezzanine for service in both directions\",\n",
+    "        [plat(direction=\"both directions\")]\n",
+    "    ),\n",
+    "    TestCase(\n",
+    "        \"125 St & St Nicholas Ave (SW corner) to mezzanine for service in both directions\",\n",
+    "        [plat(direction=\"both directions\")]\n",
+    "    ),\n",
+    "]\n",
+    "\n",
+    "for test in tests:\n",
+    "    print(\"===========\")\n",
+    "    print(test.case)\n",
+    "    rez, err = parse(test.case)\n",
+    "    test.check(rez, err)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": []
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "alphastudio": {
+   "as_jupyter_image_name": "gcr.io/ts-quantsource/as-jupyter-v6",
+   "as_jupyter_image_tag": "f5cc425e18e2"
+  },
+  "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": "3.6.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 4
+}