Missing Pretty instance for Doc itself

[Javran]

should be a straightforward pPrint = id. I'm wondering if there is a particular reason behind not implementing this instance?

[jwaldmann]

Depends on what behaviour you expect.

Going by the definition https://hackage.haskell.org/package/pretty-1.1.3.5/docs/Text-PrettyPrint-HughesPJClass.html "simlar to Show but nicer looking" I'd expect the contract for Show,

in particular, sth. like "read . show == id". Note that pPrint "foo" gives "foo", not foo.

And I'd not expect Doc things to be readable. Things produced by pPrint, yes - but general Doc, no.

[jwaldmann]

see also #37 for other possible instances of Pretty