[Haskell] ANN: wl-pprint-1.0: Wadler/Leijen pretty printer

Stefan O'Rear stefanor at cox.net
Sun Apr 15 19:45:43 EDT 2007

On Mon, Apr 16, 2007 at 12:10:01AM +0100, Joel Reymont wrote:
> On Apr 15, 2007, at 8:19 PM, Stefan O'Rear wrote:
> > PPrint is an implementation of the pretty printing combinators
> > described by Philip Wadler (1997). In their bare essence, the
> > combinators of Wadler are not expressive enough to describe some
> > commonly occurring layouts. The PPrint library adds new primitives to
> > describe these layouts and works well in practice.
> Why should I use PPrint instead of the PJ/Hughes pretty printer that  
> comes with Haskell?

Wadler designed these combinators specifically in response to Hughes'
paper, and they are simpler in several ways.  There is fundamentally
only one type of concatenation, indentation is always non-negative,


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