From 11146a538c48574354e9f1f7247024cae1c6ec37 Mon Sep 17 00:00:00 2001
From: Wojciech Nagrodzki <278594+wnagrodzki@users.noreply.github.com>
Date: Sat, 4 Aug 2018 19:55:13 +0200
Subject: [PATCH] Added "Avoid force unwrapping" section

---
 README.md | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/README.md b/README.md
index 80e7c56..ca90cf4 100644
--- a/README.md
+++ b/README.md
@@ -16,3 +16,13 @@ Declare class `final` unless you explicitly design it to be inheritable. For non
 When designing a module prefer `public` for non final class unless you explicitly design it to be inheritable by external clients. For `open` class prefer `public` for members except for those you explicitly design for overriding by external clients.
 
 > Every point that can be overridden increases complexity, thus it should always be a conscious choice to add it.
+
+### Avoid force unwrapping
+
+Use `guard` and `fatalError()` instead of force unwrapping to clarify your intent.
+
+```swift
+guard let value = optionalValue else { fatalError("reason why value must be present") }
+```
+
+> This is to avoid situations in which reason for force unwrapping is undocumented.