The reason why we "unwrap" the error so late is because we want to
recover from this error, which means the file pointer has to be at the
right position. Unwrapping early would leave the pointer in the middle
of an event, which is not what we want.

If we want to bullet-proof this, it might be good to read the whole
event first into a buffer, and then read from that buffer instead.

This is not defined by arcdps, but we'd have to adjust evtclib every
time a new statechange is introduced. This way, we stay
forward-compatible.

We can always do this conversion, because we can just throw away the
events field.

The other way around is not possible, as we need a file to parse the
events from.