How to make this snippet DRY (Don't Repeat Yourself) [closed]

Question

I know it's not that bad, but I can't help but wonder if there is a way to make this DRY-er.

s = self.start
e = self.end
if s.x > e.x:
    s.x, e.x = e.x, s.x
if s.y > e.y:
    s.y, e.y = e.y, s.y

Answer 1

You basicaly want to sort your data, you may be interested in sorted then:

start = self.start
end = self.end
start.x, end.x = sorted((start.x, end.x))
start.y, end.y = sorted((start.y, end.y))

Answer 2

You can make use of getattr() and setattr() built-in functions, handling any potential number of attributes to swap:

start = self.start
end = self.end

attrs = ["x", "y"]
for attr in attrs:
    start_attr_value, end_attr_value = getattr(start, attr), getattr(end, attr)
    if start_attr_value > end_attr_value:
        setattr(start, attr, end_attr_value)
        setattr(end, attr, start_attr_value)

Also note the more explicit start and end variable names in place of s and e. I've abbreviated attribute as attr, but you may go for the full word if you prefer.

---

You may then extract this into a separate method/function for reusability and readability:

def swap_attributes(start, begin, attrs):
    """Meaningful docstring here."""
    for attr in attrs:
        start_attr_value, end_attr_value = getattr(start, attr), getattr(end, attr)
        if start_attr_value > end_attr_value:
            setattr(start, attr, end_attr_value)
            setattr(end, attr, start_attr_value)

Usage:

swap_attributes(self.start, self.begin, attrs=["x", "y"])

Or may be merge_ranges would be a better name for the function (depending on the actual problem you are solving with it).