The online docs ( http://chuck.cs.princeton.edu/doc/program/ugen_full.html#Dyno ) say;
- .attackTime - ( float, READ/WRITE ) -
- .releaseTime - ( float, READ/WRITE ) -
The type should instead be "duration".
This is slightly relevant-ish as some of the STK UGens would express times in float. I think we got most of those by now but it can't hurt to keep such confusing inconsistencies to a minimum.
Yours,
Kas.