I added the test and in the process I also added a method to create s-expression terms, which I don't think was possible before (and fixed how they should be printed, which is without the commas). I had added the printing function because these terms show up in proofs, so we need to print them.
I added the test and in the process I also added a method to create s-expression terms, which I don't think was possible before (and fixed how they should be printed, which is without the commas). I had added the printing function because these terms show up in proofs, so we need to print them.