December 06, 2020 • 2 min read
I’ve been learning a bit of Python this Fall to facilitate conversations with a mentee. In this post, I’m going to share the first Python function I’ve ever written, a solution to the Exercism challenge ‘Raindrops’.
Is this good Python code? I don’t know; that’s why I’m posting it here. I’ve
$ python3 -c 'import this' yet am still gloriously ignorant. Below I’ll
share the problem, my solution, and a code self-review via praise and
Your task is to convert a number into a string that contains raindrop sounds corresponding to certain potential factors. A factor is a number that evenly divides into another number, leaving no remainder. The simplest way to test if a one number is a factor of another is to use the modulo operation.
The rules of
raindrops are that if a given number:
def convert(number): result = str(number) + " " if number % 3 == 0: result += "Pling" if number % 5 == 0: result += "Plang" if number % 7 == 0: result += "Plong" return result.split()[-1]
Starting with a very low bar, I like that this solution is compilable Python code. I think the solution is very readable. My return statement is a bit clever; it takes the last item in the string which is either some variant of the Raindrops string, or the number itself as a string. I’ve done this exercise in a few languages and it’s a take I’ve never thought of before, and so I enjoy the novelty there.
I don’t like that my function argument is called
number; I took that from the
setup code but I prefer to avoid argument names that carry their type. In this
case, the input really is a meaningless number, so I’m not sure what a better
alternative would be.
I try to avoid conditionals and there are three here. I’d prefer a data structure that we can fetch from whenever possible. For the sake of speed and simplicity, I didn’t go that route, but I am sure that I will as I get more comfortable with Python.
As mentioned in the previous section,
return result.split()[-1] is clever, in
both the good and bad meanings of that word. I can imagine someone who is newer
to string manipulation struggling with that a bit. It isn’t the most
beginner-friendly code I’ve ever written.
I hope this beginner Python code was entertaining to someone. It lives online at this permalink.
Blog of Jake Worth, software engineer in Maine.