Add `remove` with a movement function

[mrkam2]

Problem/Opportunity
Sometimes it is hard to use remove because it always selects the previous node in a depth-first traversal. So after removing a selection may move arbitrarily deep in the tree structure. I propose to have an alternative version that applies a given traversal function so that you have better control over the selected node after the deletion.

Proposed Solution
(z/remove zloc z/left) selects the left sibling node after removing the current node.
(z/remove zloc z/right) selects the right sibling node after removing the current node.
(z/remove zloc z/prev) matches the current behavior.

Similar changes for z/remove* function.

[lread]

Thanks for raising this issue @mrkam2!

I agree remove can be tricky to use for the reason you described.

Your idea is interesting!

For (z/remove zloc z/left), I assume we'd throw when there is no left node?
And the same idea for (z/remove zloc z/right) when there is no right node?

[mrkam2]

I guess it could simply return nil just as movement functions do. Throwing is also an option.

…

On Fri, Mar 15, 2024, 5:17 PM Lee Read ***@***.***> wrote: Thanks for raising this issue @mrkam2 <https://github.com/mrkam2>! I agree remove can be tricky to use for the reason you described. Your idea is interesting! For (z/remove zloc z/left), I assume we'd throw when there is no left node? And the same idea for (z/remove zloc z/right) when there is no right node? — Reply to this email directly, view it on GitHub <#258 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AGXVI5QG4B632ZAZVEK3SPLYYOFR5AVCNFSM6AAAAABEY2G23KVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDAMBQG42DQNBXGA> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[shaunlebron]

I agree, I had to use remove-and-move-left for this.

EDIT: I also think it should just return nil instead of throwing, just as the movement functions do.