Perhaps, I'm fundamentally misunderstanding how pop is implemented. But my understanding is that it removes the item at the given index in the list, and returns it. If no index is specified, it defaults to the last item.

Understanding the Context

So it would seem that in the first loop it should remove 3 items from the left of the list, and in the second loop it should remove 3 items from the end of the list. Learn about upcoming changes to Gmailify & POP in Gmail Gmail will start removing support for the following features: Gmailify: This feature allows you to get special features like spam protection or inbox organization applied to your third-party email account. Learn more about Gmailify. The usual use of pop is to delete the last item from a list as you use the list as a stack.

Key Insights

Unlike del, pop returns the value that it popped off the list. You can optionally give an index value to pop and pop from other than the end of the list (e.g listname.pop (0) will delete the first item from the list and return that first item as its result). Pop-up ads and new tabs that won't go away Your Chrome homepage or search engine keeps changing without your permission Unwanted Chrome extensions or toolbars keep coming back Your browsing is hijacked, and redirects to unfamiliar pages or ads Alerts about a virus or an infected device Tips: Use Safe Browsing in Chrome Avoid malware in the future It's easiest to use Gmail on multiple email clients using IMAP. If you need to use POP instead of IMAP, set up "Recent mode." Recent mode shows your last 30 days of emails from Gmail. In your email client's POP settings page, find the "Email address" or "User name" field.

Final Thoughts

Change your POP settings so that your emails are left on the server. Apple Mail: On the "Advanced" tab, uncheck the box ...