(50g) Removing Objects From Lists Quickly

[John Keith]

(01-09-2019 08:31 PM)Thomas Klemm Wrote:  

(01-09-2019 06:29 PM)DavidM Wrote:  Difference may need some clarification, though. Am I correct in assuming that the target here is what is described on this page as the "relative complement"?

Yes.

There's also a symmetric difference:

Yes, there is.

Assuming my difference program is called DIFF:

Code:


\<<DUP2 DIFF UNROT SWAP DIFF +
\>>

I'm sure this could be greatly improved by rewriting it directly rather than in terms of DIFF, but I haven't attempted to do so yet.