Immutable Collections in NET: Why and How?

on YouTube ↗54m

" summary

Argues that replacing shared mutable state with persistent structures simplifies threading, cuts implicit context and cancels, and preserves correctness using compare-and-swap loops and ImmutableInterlocked helpers. Dives into System.Collections.Immutable implementations (copy-on-write arrays, linked-list stacks, two-stack queues, rope-like immutable lists) and microbenchmarks: inserting in the middle stays fast up to 100,000 elements for immutable lists while mutable List degrades around 10k–100k, and an immutable sorted dictionary is ~2x faster than the hash-based immutable version. Notes higher GC/memory pressure.

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" chapters (6)

1. 0:00Start
2. 1:16Code quality maintenance
3. 6:41Introduction to immutable collections
4. 7:42Motivation - Why? Where can you apply immutable collections?
5. 28:12Review well-known immutable objects
6. 47:14Inspect internal structure and performance

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