[plt-dev] Re: Release Announcement for v4.2.2

From: Ryan Culpepper (ryanc at ccs.neu.edu)
Date: Sat Oct 3 18:42:09 EDT 2009

Eli Barzilay wrote:
> The possible final release announcement is below.
> Ryan: you're the last thing I need.
> ----------------------------------------------------------------------
> PLT Scheme version 4.2.2 is now available from
>   http://plt-scheme.org/
> * DrScheme now, by default, compiles all of the files that are
>   loaded when it runs a program and saves the compiled files in the
>   filesystem.  This should lead to faster load times (not faster
>   runtimes) since it avoids re-compiling files whose dependencies
>   have not changed.
> * New Scribble libraries and documentation make it easier to get
>   started with Scribble, especially for uses other than PLT
>   documentation.  DrScheme now has better indentation and syntax
>   coloring support for Scribble languages (and generally all @-exp
>   based languages).
> * Added support for abstract contracts via the #:exists keywords.
>   This is an experiment to add support for data hiding to the
>   contract system.
> * Added `in-producer': a sequence expression makes it easy to
>   iterate over producer functions (e.g., `read').  A new
>   `scheme/generator' library creates generators that can use a
>   (parameterized) yield function.
> * HtDP langs: several primitives now consume 0 and 1 arguments in
>   ISL (and up), including `append', `+' and `*'.  In addition,
>   `make-list' was added to the primitives.
> * The API to Universe has a number of new constructs.  All Universe
>   programs should run unchanged.  The most important change is the
>   addition of `animate' as an alternative name for `run-simulation'.
>   In addition, adding the clause `(state true)' to a world
>   description now pretty-prints the state of the world into a
>   separate canvas.
> * A number of changes were made to the DeinProgramm / DMdA language
>   levels: The `check-property' and `contract' forms were added,
>   `define-record-procedures-parametric' has changed.  See the
>   documentation for details.
> * The test engine in the HtDP languages no longer warns programmers
>   when the Definitions window has no tests.
> * ProfessorJ (and related code) is no longer included in the PLT
>   distributions.  It may re-appear in the future as a PLaneT package.
> * New stuff in `syntax/parse'
>   Also `syntax/keyword'?
>   `stxclass' collection gone

"The new syntax/keyword library provides support for macros with keyword 
options. A new quick start guide has been added to the documentation for 
syntax/parse library."

The other changes either don't bear mentioning or came in after the 
release branch.


> [Note that mirror sites can take a while to catch up with the new
> downloads.]
> Feedback Welcome,
> ----------------------------------------------------------------------

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