22.9: Returning Nothing At All
- Page ID
- 88725
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Does it ever make sense for a function to return nothing? Oddly, yes: if it has a useful side effect. One side effect is printing:
Code \(\PageIndex{1}\) (Python):
def cheer_for(team):
if team != "Christopher Newport":
print("Go {} go!!".format(team))
else:
print("Uhh...no.")
cheer_for("Mary Washington")
cheer_for("Lady Eagles")
cheer_for("Christopher Newport")
Output:
Here, instead of “something = cheer_for(...)” we type plainold “cheer_for(...)”. That’s because there’s no return value to capture, so there’s no point in setting it equal to anything. We call the function just to enjoy its messages.