Matthias Görgens wrote: > > If the target of the call isn't in an appropriate state, isn't that a > > bug in the constructor that it allows you to construct objects that are > > in an invalid state? > > You should fix the object so that it is never in an invalid state rather > > than blaming the caller. > > You can't really do that with files that have been closed. > Unless you disallow manual closing of files altogether. > That being said, I'd suggest that people raise custom exception, so your > callers can catch exactly what they want to handle. > An generic exception like ValueError or the proposed InvalidStateError > could be thrown by almost anything you call in your block, instead of just > what you actually intend to catch.
I didn't say that I was talking about a file. In fact, today, I'm talking about an object that manages a subprocess. If a caller tries to call a method of the manager to interact with the subprocess when the subprocess has not yet been started or after it has been terminated, then I want to raise an appropriate exception. I am raising a custom exception, and it annoys me that it has to simply inherit from Exception when I think that an invalid state condition is a common enough kind of issue that it should have a standard exception class in the hierarchy. _______________________________________________ Python-ideas mailing list -- python-ideas@python.org To unsubscribe send an email to python-ideas-le...@python.org https://mail.python.org/mailman3/lists/python-ideas.python.org/ Message archived at https://mail.python.org/archives/list/python-ideas@python.org/message/YC62WQIXUTM3ULVA64SBXBS5YZ3M2XGT/ Code of Conduct: http://python.org/psf/codeofconduct/
