[Python-Dev] When to use EOFError?

[Serhiy Storchaka]

There is a design question. If you read file in some format or with some 
protocol, and the data is ended unexpectedly, when to use general 
EOFError exception and when to use format/protocol specific exception?

For example when load truncated pickle data, an unpickler can raise 
EOFError, UnpicklingError, ValueError or AttributeError. It is possible 
to avoid ValueError or AttributeError, but what exception should be 
raised instead, EOFError or UnpicklingError? Maybe convert all EOFError 
to UnpicklingError? Or all UnpicklingError caused by unexpectedly ended 
input to EOFError? Or raise EOFError if the input is ended after 
completed opcode, and UnpicklingError if it contains truncated opcode?

http://bugs.python.org/issue25761