| @@ -90,8 +90,13 @@ The following exceptions are used mostly as base classes for other exceptions. |
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.. method:: with_traceback(tb) |
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This method sets *tb* as the new traceback for the exception and returns |
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- the exception object. It is usually used in exception handling code like |
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- this:: |
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+ the exception object. It was more commonly used before the exception |
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+ chaining features of :pep:`3134` became available. The following example |
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+ shows how we can convert an instance of ``SomeException`` into an |
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+ instance of ``OtherException`` while preserving the traceback. Once |
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+ raised, the current frame is pushed onto the traceback of the |
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+ ``OtherException``, as would have happened to the traceback of the |
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+ original ``SomeException`` had we allowed it to propagate to the caller. |
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try: |
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... |