Here is my best guess.
I think "analog spiceman" authored that information about the REPEAT ... ENDREPEAT syntax.? Maybe he meant to write it like this:
... PWL REPEAT FOR <n> ( <t1> <v1> ... <tn> <vn> | file=<file spec> ) ENDREPEAT
... PWL REPEAT FOREVER ( <t1> <v1> ... <tn> <vn> | file=<file spec> ) ENDREPEAT
In other words, you have a choice between either the time,value list, OR a filename.? I think that's why he used a "|" character there, to show that you have a choice between options -- and somehow the first one got edited out, as well as the "file=" in the second choice.? But the "|" character itself is NOT part of the syntax.
I don't know; but it works for me.
Andy