partial_manager.ipynb

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   "id": "increasing-senegal",
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   "source": [
    "class partial_manager(object):\n",
    "    # NB: Named as a function instead of a class, since it gets used as though\n",
    "    #     it was a function.\n",
    "    def __init__(self, fn, *args, **kwargs):\n",
    "        self._fn = fn\n",
    "        self._args = list(args)\n",
    "        self._kwargs = dict(kwargs)\n",
    "        \n",
    "    def __enter__(self):\n",
    "        return self\n",
    "    \n",
    "    def __exit__(self, exc_type, exc_val, exc_tb):\n",
    "        return self._fn(*self._args, **self._kwargs)\n",
    "    \n",
    "    def __call__(self, *values):\n",
    "        self._args += values\n",
    "    \n",
    "    def __getattribute__(self, attr_name):\n",
    "        if attr_name in ('_fn', '_args', '_kwargs'):\n",
    "            return super().__getattribute__(attr_name)\n",
    "\n",
    "        def accumulate_kwarg(val):\n",
    "            self._kwargs[attr_name] = val\n",
    "            \n",
    "        return accumulate_kwarg"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "id": "driving-lingerie",
   "metadata": {},
   "outputs": [],
   "source": [
    "def add(u, v, w, x, y, z, callback):\n",
    "    callback(u + v + w + x + y + z)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "id": "focused-afghanistan",
   "metadata": {},
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     "text": [
      "21\n"
     ]
    }
   ],
   "source": [
    "# Args and kwargs can both be passed when creating the partial.\n",
    "with partial_manager(add, 2, 3, y=1) as a:\n",
    "    # Calling the partial afterwards allows for adding additional args and kwargs.\n",
    "    a(4, 5)\n",
    "\n",
    "    # Kwargs can also be added by referring to them as attributes.\n",
    "    a.z(6)\n",
    "    \n",
    "    # In particular, this allows for passing callables to the original function\n",
    "    # by using decorator syntax. This is especially nice for passing multi-line lambdas.\n",
    "    @a.callback\n",
    "    def callback(ret):\n",
    "        print(ret)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "white-terrain",
   "metadata": {},
   "outputs": [],
   "source": []
  }
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