[plt-scheme] PLT Scheme v4.0

From: Michael Vanier (mvanier at cs.caltech.edu)
Date: Thu Jun 12 04:22:21 EDT 2008

Hmm.  I just compiled and installed PLT Scheme 4.0 from source on my Linux box.  Then I tried to go
through the tutorial at


and it failed when I tried to run the

#lang slideshow

line (I'd already switched into the module language).  The error message was:

standard-module-name-resolver: collection not found: #<path:slideshow/lang> in any of: ()

Any idea what's going on?


Eli Barzilay wrote:
> PLT Scheme version 4.0 is now available from
>      http://plt-scheme.org/
> This major new release offers many improvements over version 372, and
> we encourage everyone to upgrade.
>   * The PLT Scheme language now provides better syntax for modules,
>     better support for optional and keyword arguments to functions, a
>     more complete syntax for structure types, new syntax for list
>     comprehensions and iterations, a more complete and consistent set
>     of list operations, a more complete set of string operations, and
>     streamlined hash-table operations.
>   * The documentation has been re-organized and re-written.  New
>     tutorials and overviews offer a clearer introduction to Scheme and
>     PLT Scheme.
>   * New documentation tools help programmers create and install
>     documentation for libraries and Planet packages.  All installed
>     documentation can be read though the user's web browser, and even
>     searching within the browser works on local files.
>     The language for writing documentation is an extension of Scheme,
>     and document sources are linked to implementations through the
>     module system.  The module connection allows, for example,
>     reliable automatic hyperlinking of identifiers mentioned in
>     documentation to their specifications in other documentation.
>   * R6RS programs are supported in two ways: though the `plt-r6rs'
>     executable and through the `#!r6rs' prefix.  The latter allows an
>     R6RS library or program to serve as a PLT Scheme module.
>   * Legacy R5RS support is improved, partly through a separate
>     `plt-r5rs' executable.
>   * Pairs are immutable within the PLT Scheme language; mutable pairs
>     (which are the same as R6RS and R5RS pairs) are provided as a
>     separate datatype.  For more information, see
>       http://blog.plt-scheme.org/2007/11/getting-rid-of-set-car-and-set-cdr.html
>   * ProfessorJ uses a new and improved parser, it evaluates programs
>     faster, and it includes a Java-specific indenter.
>   * Testing frameworks for the HtDP and HtDC (ProfessorJ) teaching
>     languages have been unified.  Both support systematic unit testing
>     in a comprehensive fashion.  When programs lack tests, students
>     are asked to add test cases.  When all tests succeed, a simple
>     message says so; otherwise, a pop-up window (dockable) displays
>     URLs to the failed test cases and explains why the cases failed.
>   * Typed Scheme, a statically typed dialect of Scheme, is now
>     included with PLT Scheme.  While Typed Scheme is still in its
>     early stages of development, it supports modular programming with
>     types and full interaction with existing untyped code.  Safe
>     interactions between typed and untyped modules are enforced via
>     contracts.  Typed Scheme also features a novel type system
>     designed to accommodate Scheme programming idioms.  For more
>     information, see http://www.ccs.neu.edu/~samth/typed-scheme/ .
> Feedback Welcome,

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