try and except block for raising value error

Question

I am working on a deduct amount function and it should raise a run time error if a < b in value:

here is my code

def deduct_amount(a, b):
    try:
        b - a < 0
    except ValueError:
        print(a + ' can not be less than' + b)
    else:
        c = a - b
        return c


deduct_amount(8, 12)

I know my try statement is faulty. how can I throw a value error if a is less than b

You don’t need a try block to raise an error. See https://stackoverflow.com/q/4393268/217324 — путин некультурная свинья, Oct 10 '21 at 03:29
Does this answer your question? [Manually raising (throwing) an exception in Python](https://stackoverflow.com/questions/2052390/manually-raising-throwing-an-exception-in-python) — rustyhu, Oct 10 '21 at 03:44

Jab · Answer 1 · 2021-10-10T03:46:23.073

5

A try/except block is to catch an exception. You want to raise an exception:

if a > b:
   raise ValueError("a must be less than b")

edited Oct 10 '21 at 03:46

answered Oct 10 '21 at 03:30

Jab

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try and except block for raising value error

1 Answers1