Assertions¶

When to use vs throwing an Exception¶

Only to help other devs

documenting your understanding of the code at a point
- guarantees about
  - inputs (preconditions)
  - program state (invariants)
  - outputs (post-conditions)
  - like CSC494 & contracts
debugging a broken algo

if condition1:
    pass
else:
    assert False, (
    "This should never happen, but it does sometimes."
    "We're trying to figure out why. Email us if you hit this!")

When to not use assertions¶

data processing
data validation
error handling
assertions are usually disabled in prod
- performance
don't cause side-effects in assertions

assert treeDepth() == 7;

Last update: 2023-04-24