Programming Languages

In this article, we’ll discuss a small but practical question: when should you use each kind of function parameter type? Classifying Parameters Suppose we have a type T (to keep things simple, T here is not a generic type parameter). How many ways are there to pass a parameter of this type to a function? Let’s break it down: Qualifier: const-qualified or not Reference category: by value, by lvalue reference, by rvalue reference Based on this classification, we get exactly 5 parameter types:...

Let’s have some fun with templates this time. C++ has std::integer_sequence, which lets you define compile-time integer sequences. For example: #include <utility> using my_seq = std::integer_sequence<int, 1, 2, 3, 4, 5>; Now let’s write a seq_sort_t trait that performs compile-time sorting, something like: using my_seq = std::integer_sequence<int, 2, 5, 3, 1, 4>; using sorted_my_seq = seq_sort_t<my_seq>; // std::integer_sequence<int, 1, 2, 3, 4, 5> Let’s start with some groundwork. Runtime Output Use type extraction to convert std::integer_sequence into a runtime std::initializer_list for easy output....

By “environment variables,” I mean more than just shell variables. I’m referring to the variables that each process possesses and can access through system APIs. Of course, shells typically provide ways to manipulate environment variables, and we often manage them through a shell. But shell variables and environment variables are not exactly the same thing, and the two concepts can easily be confused. Let’s try to untangle them here. 1. Environment Variables From a program’s perspective, environment variables are simple....

1. Introduction I’ve been working on a C++ project recently and had to learn CMake. Honestly, CMake’s quirky syntax can be quite intimidating at first. But once you get hands-on, you’ll find that only a small subset is needed day-to-day, and it generally follows predictable patterns. Master this subset and you can likely organize a fairly large project. That’s exactly what this tutorial aims to cover. Of course, you’ll need to understand compilation and linking before reading this....