lambda.ipynb

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   "execution_count": 8,
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    {
     "data": {
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       "3"
      ]
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     "execution_count": 8,
     "metadata": {},
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   "source": [
    "(lambda x: x + 1)(2)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [
    {
     "data": {
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       "6"
      ]
     },
     "execution_count": 9,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "plusone = lambda x: x + 1\n",
    "plusone(5)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Full name: Guido Van Rossum'"
      ]
     },
     "execution_count": 10,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "full_name = lambda first, last: f'Full name: {first.title()} {last.title()}'\n",
    "full_name('guido', 'van rossum')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "6"
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     },
     "execution_count": 11,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "(lambda x, y, z: x + y + z)(1, 2, 3)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {},
   "outputs": [
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     "data": {
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       "6"
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     "execution_count": 12,
     "metadata": {},
     "output_type": "execute_result"
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   ],
   "source": [
    "(lambda x, y, z=3: x + y + z)(1, 2)"
   ]
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   "execution_count": 13,
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   "outputs": [
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      "text/plain": [
       "6"
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     "execution_count": 13,
     "metadata": {},
     "output_type": "execute_result"
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   ],
   "source": [
    "(lambda x, y, z=3: x + y + z)(1, y=2)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "6"
      ]
     },
     "execution_count": 14,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "(lambda *args: sum(args))(1,2,3)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "6"
      ]
     },
     "execution_count": 15,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "(lambda **kwargs: sum(kwargs.values()))(one=1, two=2, three=3)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "6"
      ]
     },
     "execution_count": 18,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "(lambda x, *, y=0, z=0: x + y + z)(1, y=2, z=3)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "6"
      ]
     },
     "execution_count": 19,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "closure = lambda x: lambda y: lambda z: x + y + z\n",
    "closure(1)(2)(3)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "**evaluation time**"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "one\n",
      "two\n",
      "three\n",
      "-\n",
      "three\n",
      "three\n",
      "three\n",
      "-\n",
      "one\n",
      "two\n",
      "three\n"
     ]
    }
   ],
   "source": [
    "numbers = 'one', 'two', 'three'\n",
    "\n",
    "def wrap(n):\n",
    "    def f():\n",
    "        print(n)\n",
    "    return f\n",
    "\n",
    "def_funcs = []\n",
    "lambda_funcs = []\n",
    "lambda_funcs_w_default = []\n",
    "\n",
    "for n in numbers:\n",
    "    def_funcs.append(wrap(n))\n",
    "    lambda_funcs.append(lambda: print(n))\n",
    "\n",
    "for n in numbers:\n",
    "    lambda_funcs_w_default.append(lambda n=n: print(n))\n",
    "\n",
    "for f in def_funcs: f()\n",
    "print('-')\n",
    "for f in lambda_funcs: f()\n",
    "print('-')\n",
    "for f in lambda_funcs_w_default: f()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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