[racket] Creating a #lang language, and modifying contract system

Hi again Robby,

I really don't know much about continuation marks. I want the value A to be
embedded on the exception structure, because I check that value with a
modified with-handlers macro. I thought that using parameters A will behave
like a dynamically scoped identifier.

What are the differences, if any, of using continuation marks versus using
parameters??

Thanks

2011/8/9 Robby Findler <robby at eecs.northwestern.edu>

> Could you put the value into a continuation mark and then, when you
> catch the exception, look in the continuation marks to get it out
> again?
>
> Robby
>
> On Tue, Aug 9, 2011 at 3:56 PM, Ismael Figueroa Palet
> <ifigueroap at gmail.com> wrote:
> >
> >
> > 2011/8/9 Robby Findler <robby at eecs.northwestern.edu>
> >>
> >> On Tue, Aug 9, 2011 at 3:01 PM, Ismael Figueroa Palet
> >> <ifigueroap at gmail.com> wrote:
> >> > 2011/8/4 Robby Findler <robby at eecs.northwestern.edu>
> >> >>
> >> >> The blame assignment stuff is wired pretty deep into the contract
> >> >> system. There isn't currently any way to change that aspect of the
> >> >> system without doing what you've done below.
> >> >>
> >> >> If you can say more about how/why you want to change it, tho, there
> >> >> maybe some extension to the current API that would work for you and
> >> >> that we'd be willing to maintain going forward.
> >> >
> >> > I defined a new-exn struct to represent exceptions and defined a raise
> >> > macro
> >> > that wraps Racket's raise to throw a new-exn value. Also, I need to
> >> > raise
> >> > the exception thrown by raise-blame-error inside a parameterize
> >> > expression.
> >> > I want to access and modify a parameter that will be used to construct
> >> > the
> >> > new-exn value.
> >>
> >> It sounds like you're maybe adding a field to the exn record? Can you
> >> say more about what that field is and how you compute its value? (Or
> >> if I'm just wrong about that?)
> >
> > Yes, the end result I want is to tag the exn record with a value. That
> value
> > is stored in a parameter A. I want to make raise-blame-error to always
> raise
> > an exception tagged with A+1.
> >
> > --
> > Ismael
> >
> >
>



-- 
Ismael
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