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Python

Posted by Marquis Hurley
Marquis Hurley
631 Points

exceptions and raising ValueErrors

are there any ways to determine when one is supposed to use the 'expcept' versus the 'raise'? im not totally sure when to use either. i get them mixed up.

1 Answer

Steven Parker
Steven Parker
243,266 Points
Steven Parker
Steven Parker
243,266 Points

The "raise" statement creates an exception, and the "except" statement is what responds when one is created.

One way to think about it is "raise" raises a flag, and "except" is the guy watching for it who does something when he sees it.

Marquis Hurley
Marquis Hurley
631 Points

I'm sorry but I still don't understand. I still don't really see the difference between the two. I get that "except" is, what on alert in a sense? But can it be used without ever writing the raise part? And vice versa?

Steven Parker
Steven Parker
243,266 Points
Steven Parker
Steven Parker
243,266 Points

Think of "raise" as a "sender" and "except" as the "receiver".

Certain error situations do a "raise" automatically, so an "except" can be useful for handling those even if you don't program "raise" yourself.