[racket-dev] scribble interaction

It's not the default because most examples don't need pretty printing,
and initializing a sandbox with the pretty printer takes twice as long.

At Sun, 28 Aug 2011 12:05:51 -0400, Matthias Felleisen wrote:
> 
> Shouldn't the pretty-print version be the default one? How often would I want 
> to write documentation that doesn't pretty print? 
> 
> -- Matthias
> 
> 
> 
> On Aug 27, 2011, at 4:07 PM, Matthew Flatt wrote:
> 
> > At Sat, 27 Aug 2011 13:22:12 -0400, Matthias Felleisen wrote:
> >> 
> >> When you run this program, you don't get the pretty printing you get in 
> plain 
> >> Racket or in Dr. Why? 
> > 
> > The default evaluator for `interaction' is analogous to
> > 
> > racket -l racket/base -i
> > 
> > where `pretty-print' isn't installed as the printer.
> > 
> > The example below illustrates how to install pretty printing into an
> > `interaction' sandbox.
> > 
> > ----------------------------------------
> > #lang scribble/manual
> > 
> > @(require scribble/eval)
> > 
> > @(define ex-eval (make-base-eval))
> > @(interaction-eval
> >  #:eval ex-eval
> >  (begin
> >    (require racket/pretty)
> >    (current-print pretty-print-handler)))
> > 
> > @interaction[ 
> > #:eval ex-eval
> > (define (f x)
> >   `(,(build-list x add1)
> >     ,(build-list x add1)))
> > (f 20)
> > ]
> > 
> > @(close-eval ex-eval)
> >