[plt-scheme] scribblings on PLT Scheme 4.0

From: Jens Axel Søgaard (jensaxel at soegaard.net)
Date: Thu May 24 12:53:36 EDT 2007

Jacob Matthews skrev:
> In general, the more quickly PLT Scheme versions break backwards
> compatibility the less useful old code is, on PLaneT and elsewhere.
> But in the particular case of making pairs immutable by default, it
> doesn't look like this will be a major source of incompatibility for
> PLaneT packages: only 30 modules (not packages, module files) in all
> most-current-versions of PLaneT packages (1359 total) contain any uses
> of set-car! or set-cdr!.

In principle we don't know whether users of the PLaneT packages
mutate the lists returned.

Jens Axel Søgaard

Posted on the users mailing list.