Functional Parameters in Python: Building More Flexible Code Solutions
In the world of Python programming, understanding the difference between positional and keyword-only arguments is crucial for writing clean, efficient, and error-free code.
Positional arguments are the traditional method of passing arguments to functions, where the order of the arguments matters. For instance, if a function is declared with two arguments, 'a' and 'b', the values passed during the function call should be in the same order. Changing the order can lead to unexpected output, as demonstrated in Example 1:
```python def example_1(name, age): print(name, age)
example_1('20', 'Prince') # Output: 20 Prince (incorrect) example_1(name='Prince', age='20') # Output: Prince 20 (correct) ```
In contrast, keyword-only arguments offer the benefit of getting the correct output regardless of the order of arguments, as long as the logic of the code is correct. Python supports keyword-only arguments, a method of passing arguments by using the parameter names during the function call. Here's an example:
```python def example_2(a, b, *, keyword_arg): print(a, b, keyword_arg)
example_2(1, 2, keyword_arg=3) # Output: 1 2 3 example_2(keyword_arg=3, a=1, b=2) # Output: 1 2 3 (still correct) ```
It is recommended to use keyword-only arguments to avoid issues with argument order. Changing the order of positional arguments can lead to unexpected output, while keyword-only arguments allow for flexibility in passing arguments, as the order of arguments does not affect the output, as long as the logic of the code is correct.
Positional-only arguments are passed in the order of parameters, with the order defined in the order of function declaration. In the case of positional-only arguments, the order of arguments passed during function call must match the order of function declaration. In keyword-only arguments, the order of parameter names can be changed to pass the argument(s).
While the search results do not provide information about who wrote the example of keyword-only arguments in Python, it's clear that understanding and utilising these features can greatly improve the readability, maintainability, and robustness of your Python code.
