[scythe]

>you will not change the fact that it's slow by giving -1.

...but you can change the fact that it's slow by contributing code to the interpreter! Actor-based concurrency and prototype objects can both be made fast, as has been proven by Erlang and Lua respectively. Exceptions are an unfeature but they can be easily avoided.

The slowness of Io should be seen as a programming challenge, not a problem. ^,~