[racket-dev] patch for make-base-eval

> A namespace is a mapping from top-level identifiers to whatever they are, as
> well as a separate mapping from module names to modules (roughly). What you
> care about here is the second mapping, but you're checking the first with
> the patch.

Thanks for the explanation. That helps a lot. So the danger with my
check is when someone has another definition of pretty-print handler
but racket/pretty has not been attached?

But given the context, ie the dynamic require on the next line, it
seems like there's already an assumption about what the identifier I'm
checking is, so in this specific situation, isnt my check sufficient?



>
> Robby
>
>
> On Wed, Oct 2, 2013 at 2:45 PM, Stephen Chang <stchang at ccs.neu.edu> wrote:
>>
>> > Whether that identifier exists in the namespace has nothing to do with
>> > whether racket/pretty can be attached.
>>
>> Can you explain this a little more because it's a little unintuitive to
>> me?
>>
>>
>> >
>> > One option would be for install-pretty-printer! to just catch and
>> > discard
>> > the error. Evaluators for some languages would mysteriously not have
>> > pretty-printing turned on by default.
>> >
>> > Another option would be to attach racket/pretty before requiring the
>> > initial
>> > language for the namespace.
>> >
>> > Another option is use #:pretty-print? #f when attaching racket/pretty
>> > would
>> > fail.
>> >
>> > Ryan
>> >
>> _________________________
>>   Racket Developers list:
>>   http://lists.racket-lang.org/dev
>
>