[plt-dev] Release Announcement for v4.2.1, second call

Below are the pending announcement items, followed by items I have so
far.  Please mail me new items and/or edits.

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[Matthew]
* fixed problem with installation of docs in planet packages
  (adjust planet client to handle nested planet invocations by
  re-building the doc index only once)
* delete/backspace issue in DrScheme/MrEd
* identifier-prune-lexical-context (4.2.0.2)
  syntax-local-lift-values-expression (4.2.0.3)
  syntax-local-lift-provide
* safe-for-space fixes for the interepreter
* expose and support unreadable symbols
* Various efficiency improvements to keyword arguments.
* better interaction of HtDP languages with scheme/match

[Ryan]
* macro-debugger stuff (disable lift errors; fixed opaque variable
  ref bug)
* syntax/parse and syntax/id-table libraries

[Sam]
* typed-scheme stuff ("paths branch")

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* Redex: added `define-relation' and generalized patterns that
  appear in "where" clauses to use the full Redex pattern matcher.
  (This is a backwards incompatible change, but one often
  requested; see the Redex release notes for details.)

* The Web Server's serializable closures are now available for
  other purposes through the web-server/lang/serial-lambda
  library.

* Teachpacks: small changes to universe portion of the
  "universe.ss" API, plus the addition of a form for launching
  many (communicating) worlds simultaneously.  Bug fixes
  concerning conversion to strings.

* It is now possible to create custom scribble readers with a
  command characters different than `@', see
  `make-at-reader/inside' and `make-at-reader'

* Note: this is likely to be the last release that includes a
  solaris distribution.  If you need these builds, or if you have
  access to a (Sparc) Solaris machine than can be used in PLT
  builds, then please let me know.

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-- 
          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                    http://barzilay.org/                   Maze is Life!