BOOK / SOURCE & READING RECORD
Advanced C++ Metaprogramming
Davide Di Gennaro
2011 CreateSpace edition, ISBN 9781460966167 (not the differently titled 2015 Apress book)
Advanced C++ Metaprogramming
Actually finished the two-page sample of §5.2.2 Concept traits provided by the author, and pages 405–408 of the bonus-chapter PDF (§9.3.2 ending and §9.3.3 More on the double wrapper technique). The bonus file is not a whole chapter; the range is not exaggerated based on the name. The rest of the main text was not obtained; the table of contents was only used to check structure, and the retail and Google Books pages have only metadata and were not treated as main text.
Edition, actual reading range, and original sources →Sources
- Author's blog and sample-download entry
The author published the §5.2.2 sample and bonus PDF; the blog product description does not count as main text.
- Author's announcement of the fixed bonus-chapter link
The linked four-page PDF is actually only book pages 405–408.
- Author's public Concept traits sample
Complete two pages of §5.2.2; the same call syntax of traits can be implemented by different entities.
Syntax can be adapted; semantics still must be agreed
Author sample §5.2.2 Concept traits, two pages; bonus §9.3.3, book pages 405–408
The Concept traits sample shows an easily overlooked fact: a call expression that looks the same may be fulfilled by a static function, a function object, construction, or conversion. What generic code should really depend on is the effect that follows once the expression is valid, not an imagined assumption that the other party used a particular kind of declaration. This freedom also needs bounds; hiding resource release inside an implicit conversion may demonstrate language capability, but it makes code review hard to see side effects. Another bonus sample uses a classic C++ wrapper to prevent mixing different enumerations; today one usually just chooses enum class. My modern trade-off is to write the call shape with requires, adapt external types with a few explicit traits, and describe semantics that concepts cannot prove with documentation and assertions. The historical concept traits here cannot be called the same language feature as C++20 concepts.
Related fundamentals
Type traits and if constexpr compile-time branchingConcepts and requires: Constraining Callable InterfacesTemplate deduction: match parameters first, then instantiate code