Racket v8.16

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• Racket has expanded support for immutable and mutable treelists:
  • A variety of new treelist utility functions are available: treelist-filter, treelist-flatten, et cetera.
  • The mutable-treelist-prepend! function allows prepending to mutable treelists.
  • Mutable treelists are serializable.
• The serialize-structs module allows the minimization of dependencies by providing only a handful of core forms.
• The flbit-field function allows access to the binary representation of IEEE floating-point numbers.
• The top-left search box in the documentation works once more.
• The XML reader is 2-3x faster on inputs with long CDATA and comments, and avoids some internal contract checks to obtain a 25% speedup on large documents generally.
• The pregexp syntax includes "\X" to match a grapheme cluster), following Perl and PCRE.
• The read-json* and write-json* functions allow customization of the Racket representation of JSON elements, eliminating the need for a separate "translation" pass.
• Racket has new port I/O functions:
  • The open-input-nowhere function creates an empty input port.
  • The pipe-port? function makes it possible to determine whether a port is created by make-pipe.
  • The port-file-stat function allows gathering information about the file that is the source or target of a file-stream port.
• A revised representation of pointers improves the performance of foreign function calls. As a result, ptr-ref and ptr-set! are substantially faster.
• In anticipation of the fifteenth RacketCon, the fifteenth function returns the fifteenth element of a list.
• Racket has an improved multi-line convention for error messages.
• The db library allows prepare on virtual statements.
• The student-t distribution is part of the math/distributions library.
• Expeditor supports customizing the prompt, using the #:prompt keyword argument to call-with-expeditor.
• There is a guide to adding internationalization for a new (human) language.
• Optimizations to racket/profile improve asymptotic speed for very large call graphs.
• The #lang htdp/asl language incorporates Graphical Debugger support.
• There is lots of new documentation, and many defects repaired!

The following people contributed to this release:

a11ce, Alex Knauth, Alexander Shopov, Alexis King, Andrew Mauer-Oats, Anthony Carrico, Bert De Ketelaere, Bob Burger, Bogdan Popa, D. Ben Knoble, David Van Horn, Gustavo Massaccesi, halfminami, Hao Zhang, Jacqueline Firth, Jinser Kafka, JJ, John Clements, Jörgen Brandt, Kraskaska, lafirest, Laurent Orseau, lukejianu, Marc Nieper-Wißkirchen, Matthew Flatt, Matthias Felleisen, mehbark, Mike Sperber, Noah Ma, Onorio Catenacci, Oscar Waddell, Pavel Panchekha, payneca, Robby Findler, Sam Phillips, Sam Tobin-Hochstadt, Shu-Hung You, Sorawee Porncharoenwase, Stephen De Gabrielle, Wing Hei Chan, Yi Cao, and ZhangHao.

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