Racket 8.17

Вышел релиз самой популярной реализации Схемы.



We are pleased to announce Racket v8.17 is now available from https://download.racket-lang.org/. As of this release:

The new drracket-core package provides a version of drracket with a smaller set of dependencies. Typed Racket has support for treelists. The package manager computes checksums for packages when required, allowing the use and automatic upgrade of packages without them. The bitwise-first-bit-set function returns the smallest bit that is set in the twos-complement representation of the given number. The updated dynamic-require function makes it easier to use syntax bindings by allowing a syntax-thunk (or ’eval) to be used for them. The error-module-path->string-handler parameter allows the customization of the display of module-paths in error messages. Precision of certain numeric functions (sin, cos, and others) is improved on Windows platforms by using the MSVCRT/UCRT libraries. The string-append function has improved performance and reduced memory use for long lists of strings in the Racket CS implementation. Differences are clearly noticeable for lists of length 1 million. TCP ports use SO_KEEPALIVE, instructing the kernel to send periodic messages while waiting for data to check whether the connection is still responsive. Racket code using a terminal in Windows can receive mouse events as virtual terminal characters after using SetConsoleMode. (This is also already possible on macOS and Linux.) See the tui-term package for related example code. The #:replace-malformed-surrogate? keyword can be used to specify a replacement for malformed unicode surrogates in JSON input The http-client module no longer sends “Content-Length: 0” for requests without a body. The demodularizer (compiler/demod) can prune more unused assignments. Several judgment rendering forms in Redex are replaced by functions, allowing more convenient abstraction. When a distribution includes no teaching languages, DrRacket’s language-dialog configuration moves into the preferences dialog and the “Language” menu disappears. The math library has better support for block-diagonal matrices, including both Racket and Typed Racket. The math library contains improved implementations of acos and matrix-(cos-)angle. The stepper again works for big-bang programs. There are many other repairs and documentation imprevements!