Maybe `inf` and `1/inf` are bad names for the concept the value represents. Perhaps 'overflow' and 'underflow' are better - they are error conditions that propa

Maybe `inf` and `1/inf` are bad names for the concept the value represents. Perhaps 'overflow' and 'underflow' are better - they are error conditions that propagate (when they would affect the result, e.g. `x + underflow` would have been `x` anyway, thus it is not propagated), so you can diagnose when your computation has suffered from irrecoverable precision loss.