[plt-dev] Release Announcement for v4.2, second call

From: Eli Barzilay (eli at barzilay.org)
Date: Wed May 27 03:16:17 EDT 2009

The release announcement sketch that I have so far is below, it's
closer to proper text, but more input is needed.  Note also the items
that I don't know if it's worth mentioning or not.  Please mail me new
items and/or edits.

PLT Scheme version 4.2 is now available from


* A substantial part of MrEd (the editor classes) is now
  implemented in Scheme.  [Need to say something about thousands
  of lines that were migrated etc.]

* On-demand instantiation of module phases.  [I don't know how to
  summarize that effectively.]

* A new statistical profiler is now available, currently it
  supports only a textual output, and a GUI interface will be
  added and integrated into DrScheme.  (See the "profiler" manual
  for more information.)

* The `world' teachpack is now deprecated; its replacement
  (`universe') has a new interface, using strings instead of
  symbols and chars.

* Web-server: Native continuations in serial language, soft
  state, and typos.

* The stepper can now jump to a selected program expression.

* New in `scheme/base': `hash-has-key?', `hash-ref!',
  `in-sequences', `in-cycle'; and new in `scheme': `count', `make-list'
  (from `scheme/list'), `const' (from `scheme/function')

I'm not sure that these should have an item:

* make-rename-transformer => free-identifier=? (v5.1.5.2)

* free-id=? propagation through module exports; add
  'not-free-identifier=? syntax property to disable free-id=?
  propagation; add prop:rename-transformer and
  prop:set-transformer; fix scheme/local so that local syntax
  bindings are visible to later definitions (v4.1.5.3)

* per-thread cpu timing
          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                  http://www.barzilay.org/                 Maze is Life!

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