i'm working on an old beat slicing patch and tried to find a better way for onset detection for the slices (but not realtime, should be offline rendering) and i put that into an abstraction.
it analyzes a soundfile loaded into an array. all vanilla.
here is what i have so far (including a little test file to get started).
t_onset-detection.zip
have fun and don't hesitate to post suggestions!

EDIT: found a liitle bug regarding the list function (left outlet), which didn't reset. uploaded new file, should work now...