Add (common: ans)

[michbarsinai]

To allow many ask nodes to share the same answers. Use case is "no on any of these would:...)

Structure is around:

(common:
     (no: (reject: Bah!))
     (ask: ([[[whatever 1]]])
     (ask: ([[[whatever 2]]])
     (ask: ([[[whatever 3]]])
)

[michbarsinai]

Might need to add recursive and non-recursive versions.

(common:

and

(commonRec: