Whoever has used Xcode for debugging has heard about the po command. This command is used for printing object descriptions. Whatever we write after po gets compiled into actual code and is executed in the context where the debugger has stopped. This is done twice, first to get the expression result and then to get the object description. It is actually an alias for the expression command: expression --object-description -- myVariable.
In addition to po, there is also a p command what is an alias to expression myVariable. The main difference is that it compiles and runs the expression once, does a type resolution, and then prints the result.
The third option for printing variables is the v command what is an alias to the frame command. It reads values from memory, does a type resolution (multiple times if, for example, the expression accesses properties) and prints the result. The main difference is that it does not compile and run any code when evaluating the expression, which makes it quick to run.
Based on this knowledge, as a long time po user, I have changed my approach a bit when debugging in Xcode. I start with the v command since it is the quickest to run. If v command does not work, switching to p and then to po.
If this was helpful, please let me know on Mastodon@toomasvahter or Twitter @toomasvahter. Feel free to subscribe to RSS feed. Thank you for reading.
Augmented Code 