For quite some time now, I am hoping to come across a book on modern C++ idiom as comprehensive as the Purple book by James Coplien! Finally, I got bored of the long wait and a thought came to my mind - This is Web 2.0 and open knowledge era. Why don't I start writing myself? and ask the world to contribute to it? So here we go! A new free, open book on modern C++ idioms called More C++ Idioms is taking shape on en.wikibooks.org And everyone's invited!
What new can be said about multi-dimensional arrays in C++? As it turns out, quite a bit! With the advent of C++11, we get new standard library class std::array. We also get new language features, such as template aliases and variadic templates. So I'll talk about interesting ways in which they come together. It all started with a simple question of how to define a multi-dimensional std::array. It is a great example of deceptively simple things. Are the following the two arrays identical except that one is native and the other one is std::array? int native[3][4]; std::array<std::array<int, 3>, 4> arr; No! They are not. In fact, arr is more like an int[4][3]. Note the difference in the array subscripts. The native array is an array of 3 elements where every element is itself an array of 4 integers. 3 rows and 4 columns. If you want a std::array with the same layout, what you really need is: std::array<std::array<int, 4>, 3> arr; That's quite annoying for
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