Implementing the Scala 2.13 collections

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" summary

Scala 2.13 ships a redesigned collections library that focuses on concrete implementation details: add IterableOnce for single-pass types and primitive-friendly stepper support to avoid boxing; implement an immutable, index-backed sequence (MySeq) and factories so map/filter return MySeq after refining the CC/C type parameters; wrap a Java HashMap to make MyMap and build an intMap plus a collision‑proof hash map using an ordering constraint; everything compiles and runs, with strict‑optimized traits and builders improving allocation and runtime performance.

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" chapters (14)

1. 0:00Introduction
2. 0:57IterableOnce
3. 4:22ArraySeek
4. 5:15Collection Types
5. 8:24Index Seek
6. 22:00Inheritance
7. 28:33Nonstandard collections
8. 33:09Collision proof maps
9. 33:52Strict optimized maps
10. 35:59Info Factory
11. 37:01Built from and Factory
12. 40:46Inmap Factory
13. 42:02Summary
14. 43:00QA

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