Pattern Matching: A Sneak Peek

on YouTube ↗01h 03m

" summary

Proposal P1371 r1 brings pattern matching to C++ as a statement and expression form and shows concrete syntax and semantics: P1371 r1 documents inspect blocks, inspect expression with optional trailing return type, let vs case modes to disambiguate identifiers, wildcard and structured-binding patterns, designated-field patterns, alternative patterns for variants, reference patterns (!, ?) and a user-defined extractor pattern demonstrated with CTRE regex extraction. Examples show how nested std::variant + structured bindings collapse into compact matches and how this can eliminate repetitive dynamic_cast/std::visit boilerplate; the work is a draft proposal, not yet a language change.

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" chapters (46)

1. 0:00Introduction
2. 1:42Motivations
3. 8:47Composition
4. 12:18What is Pattern Matching
5. 12:53Point Example
6. 13:36Color Coding
7. 14:01Declarative
8. 14:13A Closer Look
9. 15:09Pattern Matching
10. 17:30Patterns and Values
11. 18:55Structure
12. 20:05Expression Form
13. 20:58Multiple Returns
14. 21:48Pattern Guard
15. 24:05Disclaimer
16. 24:31Wildcard Pattern
17. 25:27Identifier Pattern
18. 26:01Wildcard
19. 26:47Expression Pattern
20. 27:43Static Concepts
21. 28:01Two Modes
22. 29:07Existing declarations
23. 31:12Repeating the P
24. 32:25Nesting into patterns
25. 33:12Richards comment
26. 33:28Structured bindings
27. 35:02Alternative Pattern
28. 36:06Constant Expression
29. 36:32Auto
30. 36:50Integral Concept
31. 37:34Polymorphic Types
32. 38:40Reference Pattern
33. 41:25Star Questionmark
34. 42:48Extractor
35. 44:30CompilerTime Regular Expressions
36. 44:49GTRe
37. 46:17QuestionMark
38. 47:05Extractors
39. 48:24Syntax
40. 50:18Visit
41. 50:53Is Pattern Matching Required
42. 52:30Double Underscore
43. 54:13Expressions vs Statements
44. 56:25wildcard patterns
45. 57:11pattern matching in C
46. 58:31best match vs first match

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