Why does std::format do that?

on YouTube ↗01h 01m

" summary

Explains why std::format is both fast and compact: implemented in msvc implementation based on {fmt}, it uses type erasure to pack arguments (avoiding combinatorial code bloat) and replaces an array-of-variants layout that costs three pointers per arg with a compact two-array store, adds an erased output iterator (fmt_buffer) that cuts ~30KB per iterator type, requires /utf-8 for big speedups, and ships in Visual Studio 2019/2022 with defect‑report fixes pending for C++20.

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" chapters (18)

1. 0:00Intro
2. 2:13Format
3. 3:58Specifiers
4. 5:49Performance
5. 8:59Implementation
6. 10:39Type erasure
7. 11:35Same code
8. 14:13Different methods
9. 15:02Format functions
10. 18:20Format arguments
11. 24:14Format arg
12. 25:36Output iterator type
13. 33:42Optimizations
14. 42:47Format Type
15. 44:26Open Source Contributions
16. 50:15Use utf8
17. 52:12Why not throw an exception
18. 55:40Signature of format

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