Following advice, I had a look at the code in the .cpp and .h files in the library. It's a very long time since I did any programming and it certainly wasn't in C or C++. That's a way of saying I didn't understand it - but I'm long in the tooth and short on brain cells these days.
Returning to my question, I now see that these files define functions not found in the IDE (is that right?) In the examples I can find such functions but have not as yet found anywhere that discloses all the new functions available or how to use them correctly. I don't very much like the idea of just including a library and copying someone else's code which is sometimes difficult for me to follow.
So, where can I find a list of functions from each library item and how to use them reliably?