[racket-dev] Release Announcement for v5.0.1

I'm not sure that any of my items make sense for a release
announcement, but if we need to give a sense that something interesting
happened toward the release, here's an attempt to collect the most
interesting changes into a couple of bullets:

  * Changes (as part of 5.0) in the `racket' language compared to the
    `scheme' language include constructor-style printing, a `struct'
    alternative to `define-struct' that fits more naturally with
    `match' and constructor-style printing, bytecode-dependency
    management via SHA-1 hashes instead of just timestamps, and a
    reorganization of `scheme/foriegn' into `ffi/unsafe' and
    associated libraries.

  * Changes to the `racket' language (since 5.0): internal-definition
    positions allow mixing expressions with definitions, full
    continuations can escape past a continuation batter, custodians can
    attempt to terminate subprocesses and subprocess groups, the JIT
    supports additional unboxing flonum operations and unsafe variants,
    and `ffi/unsafe' provides an asychronous-call mechanism to deal
    with foreign threads.


At Fri, 23 Jul 2010 20:19:18 -0400, Eli Barzilay wrote:
> Matthew:
> 
>   * sha1 functionality (default from openssl, also a racket
>     implementation)
> 
>   * `racket/foreign' (or `scheme/foreign') + `unsafe!' moved to
>     `ffi/unsafe', more ffi reorganization (mostly 4acba84b,
>     b7c18463)
> 
>   * Maybe also `struct' and related changes (new definition, struct
>     name as the constructor)?
> 
>   * async-apply support in the FFI. (768a3721)
> 
>   * full continuations can escape past a continuation barrier
>     (49ad3096)
> 
>   * internal-definition contexts allow expressions mixed with
>     definitions; the new `#%stratified-body' form can be used for
>     bodies without this feature. (54216b5c)
> 
>   * New subprocess support in custodians
>     (`current-subprocess-custodian-mode',
>     `subprocess-group-enabled')
> 
>   * Additional flonum operations with unsafe variants.
> 
>   * The racket value printer uses constructor+quote style; update
>     Guide and Quick.
> 
>   * `in-directory'.
> 
>   * `racket/set'.
> 
>   * Improved regexp stuff?
> 
>   * Chaperones (73807aef)
> 
>   * (an extensible) `raco' replaces setup-plt, mzc, etc.
> 
>   * `eprintf' and `displayln'