prodigiouspython/Chapter_4/2_Positional_Arguments.ipynb

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   "source": [
    "# Positional Arguments"
   ]
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   "source": [
    "def add(operand_1, operand_2):\n",
    "    print(f\"The sum of {operand_1} and {operand_2} is {operand_1 + operand_2}\")"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "bf5f9c59-85d5-4117-85dc-4d245750b02d",
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    "Yipeee! we have created a new function called add which is expected to add two integers values, Just kidding 😜, thanks to the dynamic typing of the Python, we can even add float values, concat strings and many more using our `add` function, but for now, let's stick with the addition of integers 😎"
   ]
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    "add(1, 3)"
   ]
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   "source": [
    "Yup, we did got our result ⭐️. what if I forget passing a value? we would see a `TypeError` exception raised 👻"
   ]
  },
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    "add(1)"
   ]
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   "source": [
    "The name **Positional arguments** itself says the arguments should be according to the function signature. But here's a deal, we can change the order of arguments being passed, just that we should pass them with the respective keyword 🙂"
   ]
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    "`Example`"
   ]
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   "source": [
    "def difference(a, b):\n",
    "    print(f\"The difference of {b} from {a} is {a - b}\")"
   ]
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    "difference(5, 8)"
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    "difference(b=8, a=5)  # Positions are swapped, but passing the objects as keywords."
   ]
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   "source": [
    "We can see in the above example that even if the positions are changed, but as we have are passing them through keywords, the result remains the same. ⭐️"
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   "source": [
    "## Position only arguments"
   ]
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   "source": [
    "We do have the power ✊ to make the user call the function's position only arguments the way we want, Thanks to [PEP-570](https://www.python.org/dev/peps/pep-0570/) for Python >= 3.8"
   ]
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   "source": [
    "The syntax defined by the PEP-570 regarding Position only arguments is as:"
   ]
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   "source": [
    "\n",
    "```Python\n",
    "def name(positional_only_parameters, /, positional_or_keyword_parameters, *, keyword_only_parameters):\n",
    "```"
   ]
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   "source": [
    "def greet(greet_word, /, name_of_the_user):\n",
    "    print(f\"{greet_word} {name_of_the_user}!\")"
   ]
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   "source": [
    "In the above example, we do have two arguments `greet_word` and `name_of_the_user` we used **`/`** to say that **Hey Python! Consider `greet_word` as Positional only Argument**"
   ]
  },
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   "source": [
    "When we try to call our function `greet` with greet_word as keyword name, Boom 💣, we get a `TypeError` exception."
   ]
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    "greet(greet_word=\"Hello\", name_of_the_user=\"Pythonist\")"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "fef13a20-caf3-4c22-b02e-6c00a7ff913d",
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   "source": [
    "Try to call our `greet` with `greet_word` as positional only argument, meaning not passing it by keyword name. We can hope that there won't be any exception raised. 😁"
   ]
  },
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    "# Calling greet function with name_of_the_user as Positional keyword.\n",
    "greet(\"Hello\", \"Pythonist\")\n",
    "\n",
    "# Calling greet function with name_of_the_user with keyword name.\n",
    "greet(\"Hello\", name_of_the_user=\"Pythoneer😍\")"
   ]
  }
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