[plt-scheme] possible discrepancy between documentation and actual usage of Typed Scheme

From: Eli Barzilay (eli at barzilay.org)
Date: Wed Jul 2 09:10:00 EDT 2008

On Jul  2, Benjamin L.Russell wrote:
> According to the screen featured on the "Typed Scheme" homepage
> (http://www.ccs.neu.edu/home/samth/typed-scheme/), it should be
> possible to select "Typed Scheme" as a language so that it comes up
> listed as "Language: Typed Scheme" in the interactions panel of
> DrScheme, version 4.0.1, english.

That page is probably outdated.

> [...]
> Further, if I choose language "Module" and then type:
> (require typed-scheme)
> in the interactions panel, DrScheme returns the following error
> message: [...]

Yes, the module language is working only with modules; and the easiest
way to get that is to start with a `#lang' line.

> I would like to choose "Typed Scheme" as a language without having
> to define a module, similarly to with the other languages listed.
> Further, I plan to use Typed Scheme increasingly in the future, and
> would appreciate a straightforward, easy way of choosing Typed
> Scheme as a default language without having to type:
>   #lang typed-scheme
> in the definitions panel every time.
> Is there any way to do this?

As of yesterday there is: if you're in the module language, and you
didn't type anything and didn't open an existing file, then you get
`#lang scheme' inserted automatically.  The text itself is a
preference that can be changed on the language configuration panel
(form the language dialog hit the "Details" button), so you can just
change that to use `typed-scheme' instead.

This is committed to svn, but no pre-build with it yet -- hopefully
there will be one later today.  (There are some technical network
issues here...)

But note that this is a very new feature, and it's possible that
things will change.  One possibility is that the text that is inserted
will be set in the preference dialog instead of the language dialog.

> Are there any plans to list "Typed Scheme" as a language, similar to
> the other languages, in the "Choose Language" dialog box in the near
> future?

The plan is to eventually use #lang lines to specify all languages,
which is more robust in many ways.  This doesn't mean that the
language dialog will go away, but it might work in a different way
(like become a `wizard' that lists and inserts a `#lang' line, or
maybe have some language insert the #lang in a hidden way -- but
that's all speculations...).

          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                  http://www.barzilay.org/                 Maze is Life!

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