Add methods for finding subsequences in a collection

[natecook1000]

Work in Progress

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Description

Methods for finding the first, last, or all ranges of a given subsequence.

Detailed Design

TK

Documentation Plan

Guide and docs to come…

Test Plan

Initial unit tests included.

Source Impact

This is an additive change only.

Checklist

• [ ] I've added at least one test that validates that my change is working, if appropriate
• [ ] I've followed the code style of the rest of the project
• [ ] I've read the Contribution Guidelines
• [ ] I've updated the documentation if necessary

[CTMacUser]

You could probably generalize the Collection.firstRange(of:) method (and therefore BidirectionalCollection.lastRange(of:) too) with an equivalence predicate and/or letting the collections differ in Element type. The given predicate would be allowed to throw.

[karwa]

Have you seen @milseman ’s CollectionSearcher prototype? https://forums.swift.org/t/prototype-protocol-powered-generic-trimming-searching-splitting/29415

I wonder if that would serve as a useful base to include in this library. We could implement things like the generic 2-way search algorithm and Z algorithm mentioned in that post.

[natecook1000]

@CTMacUser and @karwa Absolutely, still exploring the API surfaces here. Thanks!

[natecook1000]

@swift-ci Please test

[natecook1000]

This functionality is handled by the string-processing package.