Embracing User Defined Literals Safely for Types that Behave as though Built-in

on YouTube ↗01h 03m

" summary

Shows exactly how to write and choose among cooked, raw, template and string UDLs, using real code: a base‑3 numeric parser turned into a compile‑time operator""_3 template with overflow checks via static_assert, an IP v4/v6 detector that selects return type, a compile‑time fixed‑point constructor, and chrono/unit examples. Covers practical tools—consteval vs constexpr, non‑type char template packs, namespace literal idiom—and failures like implicit octal confusion and negation-before‑UDL producing below‑zero temperatures. C++17 recipes and C++20 improvements are contrasted; implementations and pitfalls are shown, not just theory.

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" chapters (36)

1. 0:00Start
2. 1:10literal in C++
3. 3:48About me
4. 4:22Coming soon to a bookstore near you!
5. 5:21What is a user-defined literal (UDL)?
6. 7:20Anatomy of a UDL
7. 8:55Restrictions on UDLS
8. 12:10So, aren't UDLs just syntactic sugar?
9. 12:57The UDL operator
10. 13:40Namespaces for literals
11. 14:54Cooked UDL operators
12. 17:46Cooked UDL examples
13. 23:13Raw UDL operator example: Base 3 int
14. 25:41Base 3 int with error detection
15. 28:00Force compile-time error detection
16. 28:49Raw UDL operators: Nota Bene
17. 29:53Numeric UDL operator templates
18. 32:01Base 3 int revisited (helper templates)
19. 36:28UDL operator templates: Nota Bene
20. 38:10String UDL operator templates
21. 39:47Example of a usable structural type
22. 43:09IP addresses (continued)
23. 44:22About UDLs in the standard library
24. 45:06String UDLS
25. 45:42Imaginary number UDLS
26. 46:53Chrono duration UDLS
27. 48:21The problem: type sinks
28. 50:05Strong typedefs: the solution
29. 52:20Extended numeric types
30. 54:36Special-format string-like classes
31. 55:06Physical units (continued)
32. 56:09Can you obfuscate that better?
33. 57:09A lot of work to support "magic" values
34. 58:26Wait for the sign
35. 59:13Aside: points vs. deltas
36. 59:34Conclusions

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