Like write_canonical, display/1 ignores operator declarations and
shows all compound terms in standard prefix form. For example, the command
| ?- display(a+b).
produces the following:
+(a,b)
Calling display/1 is a good way of finding out how Prolog parses a term
with several operators. Unlike write_canonical/[1,2], display/1
does not put quotes around atoms and functors.