Sample Loop -> Selection
I suspect that these commands will useful to people who used to use the ‘Apple Loop Utility’ which is no longer available. One of the more specialized tools/functions that Logic Pro X has available.
Sample Loop → Selection: The loop area (defined by the loop start and end points) is used to select a portion of the overall audio file.
The Audio File Editor Loop commands, available from the Edit menu, are ideal for use with Sampler.
You can also use these functions to generate audio files that contain the loop settings in the file header. This allows you to make full use of these files in any app that can read the loop information in the file header.