#100DaysOfCode in Python Transcripts
Chapter: Days 34-36: Refactoring / Pythonic code
Lecture: Refactoring 9: be explicit in your exceptions
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One thing that the Zen is saying is explicit is better than implicit and I want to show you that concept with a couple of examples here.
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For example, if you do a from module import *, it imports everything in your namespace if this would
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import full or bar and you define such a variable or function that will override it and that leads to very obscure box. So don't do import *.
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Make it explicit what you're importing. So from module import full, bar. Another coding horror is something like try and except pass.
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Now this is like the black hole or monster that absorbs all possible errors, muting them away and you won't see anything in return.
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So whatever happens, even if I were to interrupt the program with a control C which would raise the keyboard interrupt exception,
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that will be silenced as well so I cannot even kill my program basically. So don't do this. No bare exceptions, make it explicit.
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So a little bit better will be for example, at least I get some information, or let's divide it by 0, I'm still shouting
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and I get another error. And you see these operations lead to different exceptions so the best way to do it is to explicitly name the exceptions.
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Again, try to divide number one by number two and let's go through the different exceptions we might get.
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Here for example, if I get a ZeroDivision error, I just return 0. That's my handling of the exception. If I get a type error,
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and here I just print a message but I don't really have a way to allow this and so I just reraise the exception.
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And if something else goes wrong you still can instead of doing accept pass or accept print something you can at least
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say accept exception as variable and browse that variable. And you can send this to a log file for example.
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To have at least a little bit more information when you're debugging the problem. So now it's from the cell and call it with a string.
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And here you see that it entered the type error and I get the message related to type error and it reraised the exception and if I divide by 0,
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here we don't have to crash anymore because I explicitly handled ZeroDivision error. Printed the message and return 0.
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Great, and that concludes number 9. Explicit is better than implicit.