flerda/sumset — comment on commit d2245920f98518520cb60fe7ad3682645017fe1d
File:  line 0
By flerda:

A few comments inline on what you did with this.
I think you address all the comments.

For an example of how to use a single empty list, see 5f54c8d320b3a5c534666ef067f94517c39faf6f.