London | 25-SDC-Nov | Aida Eslamimoghadam | Sprint 2 | Implement a linked list in python

[aydaeslami]

Self checklist

• I have titled my PR with Region | Cohort | FirstName LastName | Sprint | Assignment Title
• My changes meet the requirements of the task
• I have tested my changes
• My changes follow the style guide

Changelist

Implemented a doubly linked list supporting push_head, pop_tail, and remove operations in O(1) time.

[cjyuan]

The code in linked_list_test.py expects both .next and .previous properties of the removed node to be assigned None. Currently your implementation could not pass the tests.

Note: Do you know the why it is a good practice to assign .next and .previous of the removed node to None?

[cjyuan]

Could consider delegating the node removing task to remove() -- less code to maintain.

[aydaeslami]

Thanks @cjyuan, for your helpful feedback and suggestions.

My tests were passing even without setting node.previous and node.next to None, so I didn't realize this issue was there. I've now added those lines and updated the implementation accordingly.

Do you know the why it is a good practice to assign .next and .previous of the removed node to None

I think it's a good practice because if we still have access to the removed node, we could accidentally reach other nodes through its .next and .previous links. Setting them to None makes it clear that the node is no longer part of the list and helps avoid mistakes.

Thanks again for taking the time to review it and point it out.

[cjyuan]

Changes look good.

I forgot to suggest looking into __slots__ during my previous review. Could you spend a little time reading up on it and how it can be used in class design? No changes are expected; this is just for learning purposes.

[illicitonion]

Closing PR because the SDC run has finished. Feel free to re-open if you're still working on it.