51 lines
1.4 KiB
Markdown
51 lines
1.4 KiB
Markdown
---
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title: Exceptions and Errors Handling
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---
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## Exceptions and Errors Handling
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When creating a program we can make mistakes that end with errors and the worst programs we make stop running,
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it would be even more annoying if we could not find errors in the code that we made or what was wrong.
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In simple words, errors are something that programmers avoid in making a program.
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To solve this problem in python we can use `try` and `except`
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Example:
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```python
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try:
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print("this is not a string " + 1)
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except:
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print("error")
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>>> error
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```
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And if you want to get error messages in more detail from your code, you can add arguments `except Exception as err`
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```python
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try:
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print("this is not a string " + 1)
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except Exception as err:
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print("error:\n" + str(err))
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>>> error:
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>>> must be str, not int
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```
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Two additional clauses for the try-except statement are `else` and `finally`. The `else` clause executes when the program runs successfully without any error. While the `finally` clause will always execute no matter what:
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```python
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try:
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print("this is a " + "string")
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except Exception as err:
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print("error:\n" + str(err))
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else:
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print("successfully concatenated string")
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finally:
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print("end execution")
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>>> this is a string
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>>> successfully concatenated string
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>>> end execution
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```
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More Information:
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Errors and Exceptions <a href='https://docs.python.org/3.6/tutorial/errors.html' target='_blank' rel='nofollow'>documentation</a>.
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