The development community was pretty active in November, so I found many excellent iOS Twitter tips for you.

Get ready to explore latest Xcode 9 features (and just for a moment forget about some bugs!), lots of tips on Unit Testing (which you’ve promised to start writing next year), handy LLDB details and some funny moments! Enjoy 280-symbol gems from the last month.


Twitter tip #1
This handy explanatory table will describe all “guts” that are hidden behind Pointer’s name:

Twitter tip #2
A “Golden Rule” to follow when working with Core Data/Realm and multiple threads. This way database maintenance won’t become a nightmare over time.

Twitter tip #3
A nice use-case for variable shadowing! You can use it to make sure you’re referring to the local mutable copy of an argument value instead of the original argument.

Twitter tip #4
Every journey starts with a single step. Even a unit-tests journey is achievable if you’ll follow these 3 simple rules:

Twitter tip #5
After John Sundell inspired us, you have started doing unit tests, right? 
And thanks to Arek, now you know that ⌃⌥⌘U shortcut can behave differently based on the cursor position:

Twitter tip #6
Xcode’s energy impact analyzer is really powerful. You can even estimate energy impact on iPhone X according to OLED power pattern. Not a pure tip, but good to know!

Twitter tip #7
Nice improvements in the latest Xcode 9. Now you can check system version in the runtime using `@available` keyword with Objective-C projects:

Twitter tip #8
Another great tip on the latest Xcode. Here is how to improve the UI performance by removing a single file.

Twitter tip #9
Stop updating constraints for animation when using AutoLayout. There is a better way:

Twitter tip #10
Have you ever wanted to use your fingerprint as your sudo password on Macbook Pro? Well now with this single line you can do that.

Twitter tip #11
Dictionary’s alt subscript at its best. The first version is much cleaner and also a bit faster.

Twitter tip #12
Embrace the full potential of LLDB’s e (e stands for expression) command and stop using po command all the time. This will dramatically improve your debugging experience.

Twitter tip #13
Have a hard time with LLDB expressions? With this command you can see the log output and find out what was wrong.

Twitter tip #14
Stick to this naming convention and the future you will appreciate it:

Twitter tip #15
That’s why you should avoid implicitly unwrapped optionals:

Twitter fun 🙃
And some very funny moments from the last month, just to make your working day a bit brighter:


As usual, many thanks to all the community for these hacks and gems! Let’s keep spreading the knowledge every day. The Christmas tips edition is coming soooon.

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