― Ernest Hemingway
Considering all the C++ job offers that I’ve received over the last couple of months, it looks like modern C++ (any C++ release beyond C++03) is picking up momentum, especially in embedded systems. Why embedded systems? I think it’s because C++ has always put a lot of emphasis on efficiency and thus the features offered by C++11 and C++14 not only simplify a programmer’s life but also stand a good chance of yielding more performant code. Now that C++11 and C++14 are supported by almost all contemporary compilers, there’s no reason to hold back anymore.
Alas, reading standard documents or even books on the subject is no fun. While the idea behind new features is usually easy to grasp, there are often intricacies that dim a feature’s shine. Clearly, studying books and learning about subtleties is necessary at some point, but isn’t there an accelerated way to get started (or motivated)?
Now there is, at least that’s my goal with this new project that I’ve created: The Happy Path to Modern C++. The idea is to tackle modern C++ by example not by text; that is, by code snippets that demonstrate the beauty of language features, not their nitty-gritty details.
Every code snippet can be compiled and run in a debugger to explore its behavior. Thus familiarizing (and experimenting) with modern C++ language features should be painless (maybe even fun?).
Let me show you what I mean. The following snippet (which is part of cpp11/01_core_features/core_features.cpp) introduces range-based for-loops:
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////////////////////////////////////////////////// // Range-based for-loops simplify iteration over // sequences. void test_range_based_for_loops() { vector<int> values {23, 42, 19}; for (auto v : values) { // 'v' is a local copy of item. cout << v << endl; v += 1; // Value change is lost. } for (auto& v : values) { // 'v' is a reference to an item. cout << v << endl; v += 1; // Item value updated in vector. } for (const auto& v : values) { // 'v' is a const reference to an item. cout << v << endl; // v += 1; // Error: 'v' is read-only. } } |
Just go to cpp11/01_core_features and execute
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make |
to compile the code and
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make test |
to run it.
With this set-up, it’s easy to toy around: just uncomment the line in ‘test_range_based_for_loops’ that constitutes a syntax error (the line that attempts to modify the read-only variable), rerun make and see what happens. Contrast this hands-on approach with the (fine) documentation on cppreference.com, which is exact and comprehensive (and ten times more readable than the official language standardese), but nevertheless intimidating for beginners.
Be aware that you are looking at work in progress. My aim of this first release was to cover most of C++11 and C++14 core language features as well features pertaining to classes. Obviously, a lot is still missing, like
– Const expressions
– Variadic templates
– Lambdas
– Concurrency
– Move semantics
– Regexps
Contributions to this project are more than welcome, just send me your pull requests. Please keep in mind that the overall goal is to have crisp code examples that capture the essence of features, not the ugly corner cases. When in doubt, leave it out, keep it simple, keep it beautiful.