Static metaprogramming (aka ‘template metaprogramming’) is a great C++ technique that allows the execution of programs at compile-time. A light bulb went off in my head as soon as I read this canonical metaprogramming example:
#include <iostream> using namespace std; template< int n > struct factorial { enum { ret = factorial< n - 1 >::ret * n }; }; template<> struct factorial< 0 > { enum { ret = 1 }; }; int main() { cout << '7! = ' << factorial< 7 >::ret << endl; // 5040 return 0; } If one wants to learn more about C++ static metaprogramming, what are the best sources (books, websites, on-line courseware, whatever)?
[Answering my own question]
The best introductions I’ve found so far are chapter 10, ‘Static Metaprogramming in C++’ from Generative Programming, Methods, Tools, and Applications by Krzysztof Czarnecki and Ulrich W. Eisenecker, ISBN-13: 9780201309775; and chapter 17, ‘Metaprograms’ of C++ Templates: The Complete Guide by David Vandevoorder and Nicolai M. Josuttis, ISBN-13: 9780201734843.
Todd Veldhuizen has an excellent tutorial here.
A good resource for C++ programming in general is Modern C++ Design by Andrei Alexandrescu, ISBN-13: 9780201704310. This book mixes a bit of metaprogramming with other template techniques. For metaprogramming in particular, see sections 2.1 ‘Compile-Time Assertions’, 2.4 ‘Mapping Integral Constants to Types’, 2.6 ‘Type Selection’, 2.7 ‘Detecting Convertibility and Inheritance at Compile Time’, 2.9 ‘
NullTypeandEmptyType‘ and 2.10 ‘Type Traits’.The best intermediate/advanced resource I’ve found is C++ Template Metaprogramming by David Abrahams and Aleksey Gurtovoy, ISBN-13: 9780321227256
If you’d prefer just one book, get C++ Templates: The Complete Guide since it is also the definitive reference for templates in general.