Download Racket 7.2

Racket is a development language with which other development languages ​​can be developed. In addition, you can simply develop in Racket itself. It was previously known as the PLT Scheme and comes from the Lisp-Scheme family. For the background we refer to the manifesto, written under the direction of Matthias Felleisen. The developers have released version 7.2 of Racket, with the following announcement:

Racket v7.2

Racket-on-Chez is done in a useful sense, but we’ll wait until it gets better before making it the default Racket implementation. For more information, see
http://blog.racket-lang.org/2019/01/racket-on-chez-status.html

In addition, the Racket 7.2 release includes the following improvements, which apply to both implementations:

• The contract system supports collapsible contracts, which avoid repeated wrappers in certain pathological situations. Thanks to Daniel Feltey.
• Quickscript, a scripting tool for DrRacket, has become part of the standard distribution. Thanks to Laurent Orseau.
• The web server’s built-in configuration for serving static files recognizes the “.mjs” extension for JavaScript modules.
• The `data/enumerate` library supports an additional form of subtraction via `but-not/e`, following Yorgey and Foner’s ICFP’18 paper. Thanks to Max New.
• The `letrec.rkt` example model in Redex has been changed to more closely match Racket, which led to some bug fixes in Racket’s implementation of `letrec` and `set!`.
• The racklog library has seen a number of improvements, including fixes to logic variable binding, logic variables containing predicates being applicable, and the introduction of an `%andmap` higher-order predicate.