As part of dobs, a C# CLI USD-VES converter, I wrote a library that provides the official exchange rate from the US dollar to Venezuelan Bolivars (VES). I developed the dobs app mainly for personal use and to practice building .NET applications in C#. I also took the opportunity to explore the CSharpFunctionalExtensions library. In this post, I describe this Rate Provider library, which can serve as an example use of CSharp Functional Extensions.

Going through the Rust track at exercism.org, I found the Nth Prime exercise. The exercise asks to determine the nth prime for a given integer n, considering 2 as the 0th prime. To make it more interesting, I decided to memoize the calculated primes in a table and to make the calculation thread-safe so that several primes can be computed concurrently. The implementation described here is available as a GitHub repo.

I assume the reader has some familiarity with monadic parsing in Haskell, particularly with the Attoparsec library, as well as with the diff formats parsed. For the latter, I invite you to read my previous article, where I described a grammar for diffs in these formats.