Racket v6.5

Racket version 6.5 is now available from http://racket-lang.org/

• Typed Racket and the racket/contract library generate code with lower overhead, speeding up typed/untyped interaction in a number of gradual typing programs we studied.
• Macros written using syntax-parse automatically emit more accurate error messages.
• The contract profiler captures costs from more contract combinators, including all those in the main distribution.
• Hash table and set iteration, via both existing and new non-generic sequences, is more performant, up to twice as fast on microbenchmarks.
• The Racket optimizer detects many more optimization opportunities, including when variables always hold numbers.
• The db library supports single-result CALL statements in MySQL.
• The net/dns library supports SRV records.
• The racket/unix-socket library supports listen and accept operations.

The following people contributed to this release: Adrien Tateno, Alex Knauth, Alexander Shopov, Alexis King, Andrew Kent, Asumu Takikawa, Ben Greenman, Chen Xiao, Chris Jester-Young, Daniel Feltey, Eric Dobson, Georges Dupéron, Gustavo Massaccesi, Ian Harris, Jay McCarthy, Jens Axel Søgaard, John Clements, Leandro Facchinetti, Lehi Toskin, Leif Andersen, Łukasz Dąbek, Marc Kaufmann, Matthew Flatt, Matthias Felleisen, Michael McConville, Mike Sperber, Paul Stansifer, Philippe Meunier, Robby Findler, Rodrigo Setti, Ryan Culpepper, Sam Caldwell, Sam Tobin-Hochstadt, Sorawee Porncharoenwase, Spencer Florence, Stephen Chang, Tony Garnock-Jones, Vincent St-Amour, WarGrey Gyoudmon Ju, and William J. Bowman. Feedback Welcome