Thank you for your answer. That does make some sense. On the other hand,
I am not sure I think this behaviour is reasonable. I think these two
should be equivalent:
Text.PrettyPrint.HughesPJ> text "foo" <+> empty <> text "bar"
foobar
Text.PrettyPrint.HughesPJ> text "foo" <+> text "" <> text "bar"
foo bar

I argue that (text "" == empty) and that I should be able to use them
synonymously. The point I think I'm trying to make is that I have used
this pretty printing library for a while now, and I have never had to
worry about the precedence of the operators before.

I'm not sure I agree, but if you really want that, maybe you could simply make your
own module where
empty = text ""
or
text "" = empty
test x = HughesPJ.test x

Best regards
Tomasz