Tirsvad
5af3a58578
Add src/main.py with the six debugging exercises (describe the problem, reproduce the bug, play computer, fix the errors, print is your friend, use a debugger), each with its fix noted. Document them in the README.
36 lines
1.3 KiB
Markdown
36 lines
1.3 KiB
Markdown
# 013-debugging
|
|
|
|
Day 13 of Udemy's *100 Days of Code: Python Pro Bootcamp*: finding and fixing
|
|
bugs in Python code.
|
|
|
|
All exercises live in [`src/main.py`](src/main.py), each commented out with the
|
|
fix noted beside it. Uncomment one at a time to run it.
|
|
|
|
## Exercises
|
|
|
|
| Exercise | Bug | Fix |
|
|
| --- | --- | --- |
|
|
| Describe the Problem | `range(1, 20)` never reaches 20, because the upper bound is excluded | Use `range(1, 21)` |
|
|
| Reproduce the Bug | `dice_imgs[dice_num]` raises `IndexError` when the roll is 6 | Index with `dice_num - 1` |
|
|
| Play Computer | A birth year of exactly 1994 matches no branch | Use `>=` in the `elif` |
|
|
| Fix the Errors | `input()` returns a string, so `age > 18` fails; the `print` is not indented | Convert with `int()`; indent the `print` |
|
|
| Print is Your Friend | `==` compares instead of assigning, so `word_per_page` stays 0 | Use `=` |
|
|
| Use a Debugger | `b_list.append(new_item)` sits outside the loop, so only the last item is kept | Indent it into the loop |
|
|
|
|
## Debugging approach
|
|
|
|
1. Describe the problem in your own words.
|
|
2. Reproduce the bug.
|
|
3. Play computer: step through the code by hand.
|
|
4. Fix the errors the interpreter reports.
|
|
5. Use `print()` to inspect values.
|
|
6. Use a debugger to step through execution.
|
|
|
|
## Running
|
|
|
|
Requires Python 3.
|
|
|
|
```bash
|
|
python src/main.py
|
|
```
|