Ryan Culpepper | 27 Feb 00:01 2014

Racket v6.0

Racket version 6.0 is now available from


Racket 6.0 has a new package system, including a catalog of
hundreds of already-available packages. Please visit


for an overview of the packages.

Racket versions 5.3.4 through 5.3.6 included "beta" versions of the
package system. Racket version 6.0 incorporates many improvements
suggested by preliminary experiences in those versions:

   * A package is treated as a single collection by default, so it is
     even easier to use a GitHub repository as a package. Get started

   * DrRacket includes a new package manager GUI, available via the
     File|Package Manager ... menu item. The GUI is also available
     as a stand-alone program via the "gui-pkg-manager" package.

   * The main Racket distribution has been separated into about 200
     packages. The Racket installer combines the core system with
     bundled versions of these packages.

     Alternatively, you may now install a Minimal Racket distribution
     --- which is about 1/10 the size of the main distribution --- and
(Continue reading)

Eli Barzilay | 10 Aug 14:59 2013

Racket v5.3.6

Racket version 5.3.6 is now available from


Racket v5.3.6 is a bug-fix release.  It eliminates errors from
v5.3.5 that people have found over the summer.

Feedback Welcome,

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

Eli Barzilay | 18 Jun 13:20 2013

Racket v5.3.5

Racket version 5.3.5 is now available from


This is a special-purpose release to match the arrival of "Realm of
Racket" in bookstores.  Racket v.5.3.5 adds a single `realm'
collection to the v5.3.4 release.  The new collection contains the
source code that readers of Realm may wish to use for experiments.

Feedback Welcome,

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

Eli Barzilay | 8 May 18:46 2013

Racket v5.3.4

Racket version 5.3.4 is now available from


* Extflonums (80-bit floating-point numbers) are supported on some
  x86/x86_64 platforms -- including Windows, and including platforms
  where Racket is compiled to use SSE instructions for flonum
  arithmetic.  Thanks to Michael Filonenko.

* OS X: DrRacket and all of the other apps are now signed with an
  official key.

* Tally Maze: a new game based an enumeration of 2d mazes.

* The Optimization Coach, a DrRacket plugin, has been moved from the
  Racket distribution to the Racket package repository.  Install it
  with: raco pkg install optimization-coach

* Redex: `define-union-language' now merges productions when
  languages define the same nonterminals.  Thanks to William Bowman.

* The `srfi/19' library is now compatible with the date structure
  type exported by `racket/base'.

Feedback Welcome,

          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                    http://barzilay.org/                   Maze is Life!
  Racket Announcements list:
(Continue reading)

Asumu Takikawa | 8 May 18:10 2013

[ANN] RacketCon 2013: 29 September

RacketCon 2013

We are pleased to announce that (third RacketCon) will take place on September
29, 2013 at Northeastern University in Boston.  This year, we plan to bring in
several speakers from industry, as well as host talks from Racket developers
and users.

Lunch will be provided.

On the Saturday (28th) before RacketCon, we plan to hold a hackathon to work on
various Racket projects.

Registration will open during the summer, and we will post a detailed schedule
of events around the same time. The conference website is at


Asumu Takikawa and PLT

  Racket Announcements list:

Eli Barzilay | 15 Feb 21:53 2013

Racket v5.3.3

Racket version 5.3.3 is now available from


This is a bug-fix release to address a flaw in DrRacket v5.3.2
concerning interactions between the contour window and the syntax

Feedback Welcome,

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

Eli Barzilay | 1 Feb 05:20 2013

Racket v5.3.2

Racket version 5.3.2 is now available from


Core Libraries:

* The new `math' library provides functions and data structures for
  working with numbers and collections of numbers.  Functions
  include non-elementary (such as gamma, zeta, Lambert's W),
  number-theoretic (factorization, modular arithmetic), linear
  algebra (arithmetic, decompositions), and statistical (expected
  values, order statistics, binning).  Data structures include
  arbitrary-precision bigfloats, probability distributions, and
  multidimensional arrays.

* The new `file/untar', `file/untgz', and `file/unzip' libraries
  support unpacking widely used archive formats.

* The new `lazy-require' form allows programs to delay the loading
  and instantiation of helper modules until they are needed.

* The new `data/bit-vector' library provides an implementation of
  bit vectors (a mutable sequence of booleans) supporting popcount.

* The `racket/generic' library allows the specification of default
  method implementations for core datatypes.

* The `openssl' library can verify hostnames and use the operating
  system's certificate store to verify certificates.

(Continue reading)

Eli Barzilay | 7 Nov 23:16 2012

Racket v5.3.1

Racket version 5.3.1 is now available from



* The `case' form dispatches on characters, fixnums, symbols, and
  keywords in logarithmic time.  (Thanks to Jon Zeppieri.)

* The new `racket/format' library provides new and improved
  string-formatting functions.

* Logging tools include improved filtering support based on the name
  of a logger.  A new `define-logger' form simplifies the use of
  named loggers.  Forms such as `log-debug' now support string

* The `for' forms now support `#:break' and `#:final' clauses.

* The new PLTCOMPILEDROOTS environment variable configures the
  search path for compiled bytecode.


* Check Syntax now summarizes the documentation (i.e., the blue
  boxes) for the identifier at the insertion point in the top-right
  corner of the definitions window.

* Check Syntax now runs continuously for programs that declare their
  language within the source.  This mode has been available for
(Continue reading)

Eli Barzilay | 7 Aug 15:39 2012

Racket v5.3

Racket version 5.3 is now available from


* Submodules are nested module declarations that can be loaded and
  run independently from the enclosing module.  For an overview of
  submodules, see


* The futures visualizer is a graphical profiling tool for parallel
  programs using futures.  The tool shows a detailed execution
  timeline depicting the migration of futures between threads, and
  gives detailed information about each runtime synchronization that
  occurred during program execution.  In addition, `would-be-future'
  is a special type of future that always executes sequentially and
  records all potential barricades a regular future would encounter.

* Optimization Coach (formerly Performance Report) reports
  information about Racket's inlining optimizations.  Optimization
  Coach can be launched in any language through the View menu.

* The new `images/flomap' library defines floating-point bitmaps and
  fast image processing operations on them.  It is written in Typed
  Racket, so Typed Racket code may use it without the cost of
  contract checks.

* The new `json' library supports parsing and generating JSON.
  (Originally based on Dave Herman's planet library.)

(Continue reading)

Eli Barzilay | 26 Mar 22:44 2012

Fixed Racket v5.2.1 Installers

Dear Racketeers,

We have just released a DrRacket version 5.2.1 that starts fine today.
The fixed version has replaced the 5.2.1 installers.  This version and
the original 5.2.1 differ only in this one fix.


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

Matthias Felleisen | 26 Mar 16:45 2012

Today's DrRacket problem

Dear Racket users, 

Many of you noticed that DrRacket v5.2.1 refused to launch today,
March 26.  We sincerely apologize for this inconvenience.

The problem is due to a so-called "Easter egg", which is a visual
surprise that one developer builds into the code for the others and
our users -- a tradition going back to the early days of our
project. The bug affects only DrRacket, no other Racket software.

As far as version 5.2.1 is concerned, the bug will disappear tomorrow,
but it will return later this year.  For the upcoming release -- due
out before the next "easter egg" date -- we will either install much
more reliable test methods for the Easter eggs or we will remove them

We intend to make a fixed version of 5.2.1 available later today. In
the meantime, we offer the following workarounds for the DrRacket bug:

* Revert to version 5.2:


* In your current installation of 5.2.1, navigate to the following

     collects -> drracket -> private 

  remove the file

(Continue reading)