OCR J277 2.2 / AQA 8525 programming
Validate a whole-number age between 11 and 18.
← All GCSE Python lessonsValidation checks that entered data meets stated rules before the program uses it. A range check can reject values outside an allowed interval, while a loop can ask the user to try again. Design tests for both boundaries and values outside the range.
Watch out: Validation is not verification. A value can satisfy the format rules but still be factually wrong.
Read this worked example. Predict its output, run it in Python 3, and explain how variables change.
def valid_age(text):
if not text.isdigit():
return False
age = int(text)
return 11 <= age <= 18
for sample in ["15", "-1", "nineteen", "19"]:
print(sample, valid_age(sample))Validate a whole-number age between 11 and 18. Work from the starter code before comparing with the solution.
Download starter + solution ZIP ↓For a stretch challenge: add meaningful test data, handle an edge case and explain one design decision.
def valid_age(text):
if not text.isdigit():
return False
age = int(text)
return 11 <= age <= 18
age_text = input("Enter age (11 to 18): ").strip()
while not valid_age(age_text):
print("Please enter a whole number between 11 and 18.")
age_text = input("Age: ").strip()
print("Accepted:", int(age_text))The reference is one possible approach. Test your own program before comparing.
Question: Why is checking only age >= 11 insufficient?
It would accept ages above 18, and non-numeric input could crash conversion.
Explain one test you used, one problem you solved and one improvement you would make.
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