PLT Scheme v4.1

PLT Scheme version 4.1 is now available from

  • DrScheme changes:
    • The Module language now has an automatically inserted #lang declaration, so the interactions window is available right away for new windows.
    • Searching is now interactive (see the manual for details).
    • Memory limits are now enabled by default.
  • Typed Scheme supports a novel type checking mechanism for homogeneous and heterogeneous variable-arity function definitions and applications.
  • Redex (a domain-specific language for testing operational semantics) is now included in the distribution. See also redex.plt-scheme.org.
  • Lots of improvement to the documentation, including: better searching, table-of-contents, and language-sensitive help (in the teaching languages).
  • The world.ss teachpack no longer supports end-of-time, only stop-when.
  • MzScheme has now a logging facility, search the documentationfor "logger" for more details.
  • Bug fixes:
    • begin in R5RS (and derived languages),
    • #lang planet,
    • eval works with phases.
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