Add daily email for 2025-01-17

Comments can lie. Code can't.

source/_daily_emails/2025-01-17.md

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+---
+title: Comments can lie. Code can't.
+date: 2025-01-17
+permalink: daily/2025/01/17/lies
+tags:
+  - software-development
+cta: ~
+snippet: |
+  Comments in code can lie, but the code itself can't.
+---
+
+How often have you need code like this?
+
+```php
+// Returns true.
+return false;
+```
+
+Whilst a comment like this could have been true when it was written, the code can change independently of the comment - making them out of sync and the comment no longer true.
+
+As the comment is not evaluated or executed, there isn't a way to validate whether it's still correct, so whilst it could be, it may not be.
+
+Comments should describe why the code is needed, not what it does.
+
+If a comment describes the functionality, it can be refactored and extracted to a class, method or function - a.k.a. self-documenting code.
+
+But, if you want something that will alert you if the functionality changes, look into [automated testing][0].
+
+If you have a passing test that suddenly starts to fail, you know the behaviour has changed.
+
+[0]: {{site.url}}/atdc