Template Metaprogramming: Type Traits (part 1 of 2)

on YouTube ↗01h 00m

" summary

Walks through implementing many std type traits from first principles, showing actual code patterns: integral_constant and true_type/false_type as value-and-type returns, alias helpers like underscore_t/_v for calling conventions, and remove_const via partial specialization. Explains when compiler intrinsics are required, why specializing standard templates or using incomplete types causes undefined behavior, and how C++17 auto non-type params and C++20 concepts change implementations. Examples compile and expose the precise rule that makes each trait correct.

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" chapters (12)

1. 0:00Intro
2. 0:21Intended Audience
3. 8:18Tutorial Format
4. 16:14Value Metafunctions: Sum
5. 19:09Calling Type Metafunctions
6. 21:17Convenience Calling Conventions
7. 28:37Cpp17UnaryType Trait
8. 30:18Cpp17Transformation Trait
9. 31:14Undefined Behavior
10. 33:51is_void (Unary Type Trait)
11. 44:58remove_const(Transformation Trait)
12. 53:46conditional

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