I still can't find any built in function to comment/uncomment using at the beginning of lines. However, there is a text macro that can be bound to a key combination as follows: * open Xcode preferences * go to Key Bindings * Duplicate a Key Binding Set if you don't already have a custom set * expand the Action: Edit → Insert Text Macro → C → Comment Selection * double click in the Key column * set the key combination of your choice (I suggest Command-/) * click Apply/OK * now when you select text, press Command-/ to comment the selection using /* and */ * there is no automated way to uncomment a selection that I know of