What I have done

I have extracted the interval map impl from Xline, refined this part into a crate, added detailed documentation and testing, and published it as rb-interval-map on crates.io.

Modifications to the Xline project are outlined in the first PR cited above, representing the fundamental tasks of the project I’m applying for. There’s little to discuss regarding the specific implementation, as I’ve provided ample details in the PR. Please refer to this proposal for the general idea. The specific code behavior is slightly different from what is stated in the proposal, but the idea of finding out LCA is the same.