https://sharp-sherif.xyz/tags/functional-programming/ Recent content in Functional-Programming on CHANGE_ME_BLOG_TITLE Hugo en Thu, 24 Sep 2026 00:00:00 +0300 https://sharp-sherif.xyz/posts/functional-extensions/ Thu, 24 Sep 2026 00:00:00 +0300 https://sharp-sherif.xyz/posts/functional-extensions/ <h2 id="introduction">Introduction</h2> <p>In <a href="https://sharp-sherif.xyz/result-pattern-in-csharp">an earlier post</a>, I created <code>Result&lt;TValue, TError&gt;</code>, a generic, allocation-free struct. On its own, it supports only procedural programming. Call something, check <code>Success</code> or <code>Failure</code>, branch and repeat. This is the same boilerplate as Go’s <code>if err != nil</code>.</p> <p>In functional languages, a result is a value like any other, so operations can be composed on it directly. F# includes a <code>Result</code> module for this. This post discusses extension methods that reimplement <code>map</code>, <code>mapError</code>, <code>bind</code>, <code>iter</code>, <code>iterError</code>, <code>defaultValue</code> and <code>defaultWith</code> for <code>Result&lt;TValue, TError&gt;</code>. They let you chain steps without checking <code>Success</code> or <code>Failure</code> after each call.</p>