[Feature]: Quad Collection

[oren-lava]

Summary

Implement a Quad collection to support collections with composite keys of four elements.

Problem Definition

Currently, the "collections" package supports composite keys of sizes 1-3. During development in the Lava project, I needed a collection with a composite key of 4 elements. This feature will provide extra flexibility for users of the "collections" package.

Proposed Feature

Implement a Quad collection to support collections with composite keys of four elements. It will be very similar to the Pair and Triple collections.

[tac0turtle]

is the need for a quad collection in order to provides indexes for query based data?

[oren-lava]

No. I wanted to create a new KV store using collections that will allow me to iterate over entries with a prefix of 3 elements, for performance purposes.

In the past (before the collections package existed), I've manually created KV stores that were encoded with custom bytes keys. Since the key was a bytes array, I could create a prefix of any length I wanted to.

Now, I wanted to use the collections package for its type-safety and elegance, but I was limited by the max size of composite keys - Triple.

[oren-lava]

BTW, I've already implemented the Quad collection. Given your approval, I'll open a PR.

[testinginprod]

@oren-lava feel free to open a PR, i'll be happy to review 🙏