Previously, we showed how to enable the Visual Studio IDE to work with an ostensibly cross-platform CMake project. Today we will prove that the project indeed can work on a non-Windows platform — at least as much as is possible…
Cross-platform without complexity: VS IDE
Let’s say you want to start a modern C++ project. However, you have some requirements in mind that may be hard to achieve. First, the project should support development in the Visual Studio IDE but also provide a simple command…
Switch expression performance: part 2
Previously we looked at the performance of simple switch statements and expressions. Today we will consider switch expressions with when clauses. This example shows a simple letter grade calculator as might be defined for a US high school: The first…
Switch expression performance: part 1
Being the good multi-paradigm language that it is, C# has adopted features from across the programming spectrum. One recent addition of the functional programming variety is pattern matching, first arriving in C# 7.0 with enhancements in C# 8.0. The latter…
Null operator performance
The null-conditional (AKA “Elvis”) operator and null-coalescing operators were introduced in C# 6.0 and C# 2.0 respectively. They’ve been with us for years and help make our code more concise. But have you ever wondered about their effect on performance,…
Watching a directory: debouncing
Over the last few posts, we have created a relatively full-featured DirectoryWatcher library, but it has one glaring omission. To demonstrate, let’s review the output of the sample program which randomly modifies the files it is watching: For many types…
Watching a directory: composability
Last time, I mentioned that our DirectoryTreeWatcher code demonstrates composition but not composability. To see what I mean, imagine that you wanted to add logging so you could track whenever a subscription is created or destroyed. A nice separation-of-concerns way…
Watching a directory: composition and thread-safety
We have a testable DirectoryWatcher; now what? Given that the DirectoryWatcher can only watch files in a single directory, we can extend this to a whole directory tree. Perhaps the best way to achieve this is with composition (in the…
Watching a directory: testability
Previously, I introduced DirectoryWatcher but it was woefully untestable. Tight coupling to the file system is something that would be at odds with a microtesting practice as described by “Geepaw” Hill. I agree with him and nearly always avoid extraneous…
Watching a directory: basic intro
Let’s say we want to write a .NET Core class that watches for file changes in a single directory. The implementation should only notify for explicitly subscribed files. For example, if DIR is being watched and DIR\file1.txt is subscribed, we…