The Design Patterns book by Gamma, Helm, Johnson, and Vlissides presents 23 time-tested patterns that consistently appear in well-designed software systems. Each pattern is presented with a description of the design problem the pattern addresses, as well as sample implementation code and design considerations. This paper explores how the patterns from the "Gang of Four", or "GOF" book, as it is often called, appear when similar problems are addressed using a dynamic, higher-order, object-oriented programming language. Some of the patterns disappear -- that is, they are supported directly by language features, some patterns are simpler or have a different focus, and some are essentially unchanged.
The paper is available as AI Memo AIM-2002-005, in Postscript, or PDF.
The slides for a lecture covering this material can be found at
They are also available in PDF (2.8 MB) and in Powerpoint (200 KB) formats.
Currently the code is specific to Scheme48 (see www.s48.org), but only very slightly so. Ports welcome.
GLOS, as a tar file, as of Feb. 14, 2001. The tarball includes the paper described above, in postscript and PDF versions.
To load GLOS, fire up scheme48, open the file test.scm, and paste the first five lines from test.scm at the scheme48 prompt.