ArrayDeques and How to Contribute to Scala 2.13

on YouTube ↗23m

" summary

mutable.ArrayDeque is a circular-buffer implementation that replaces many mutable Scala collections and claims faster common operations than Lists, Buffers, Stacks and Queues. It provides constant-time random access plus O(1) prepend/append/delete by keeping start/end indices and using modular arithmetic (with a power-of-two bitmask optimization). Resizing moves blocks via array.copy/memcpy (2–3 memcopies), supports clear vs clear-and-shrink to avoid GC leaks, and shows benchmarks where most ops win while random-indexing pays a small bitwise cost. Contributions welcome.

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" chapters (7)

1. 0:00Start
2. 3:23Array Decks
3. 4:00Data Structures 101
4. 7:38Implementation of an Array Attack
5. 8:04How Do I Insert an Element at the Ayat'index
6. 12:13Demo
7. 20:47Benchmarks

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