The Pony devs did chime in and mentioned that they do define division by zero to be NaN (or positive infinity) where the underlying type supports it (e.g. IEEE 754 floats).

Most integer representations have no space for such a value, so the only choices available to language developers are:

1. Throw an exception or otherwise consider it an error

2. Define the result to be 0 or 1 or some other integer value (0 being the only good choice)

3. Use a non-standard integer representation

Most languages opt for option 1, Pony chose 2, and I've never seen 3, perhaps due to it requiring so much software interference and precluding inter-operation with other languages.