On 27 October 2010 18:39, Stephen Tetley
Having a Pretty class plus primitive printers int, bool is an advantage. For ints, bools, ... code tends to look neater if you use int or bool rather than pretty. Plus for ints and others you tend to need things like hex printers anyway, so one size via a type class doesn't fit all.
Definitely agreed.
As for the class - if I have a reasonably sized syntax tree I'd rather just do
pretty a
... than formulate a naming scheme like:
prettyExpr a
What do you mean by "prettyExpr"? My main objection to having a Pretty type class is that when having a "reasonably sized syntax tree", aren't you likely to want to have your own custom printing variants rather than the ones in the pre-defined class? As such, does having a default class make sense if it isn't used? That said, 9 packages [1] do use prettyclass [2]... out of the 168 packages [3] that use pretty itself [4] (some of which implement their own Pretty class). [1]: http://bifunctor.homelinux.net/~roel/cgi-bin/hackage-scripts/revdeps/prettyc... [2]: http://hackage.haskell.org/package/prettyclass [3]: http://bifunctor.homelinux.net/~roel/cgi-bin/hackage-scripts/revdeps/pretty-... [4]: http://hackage.haskell.org/package/pretty -- Ivan Lazar Miljenovic Ivan.Miljenovic@gmail.com IvanMiljenovic.wordpress.com