Interactive SET Language, distant SETL variant widely used in discrete mathematics: downloads on lower 2/3 of page, for DOS, Mac OS, Windows; source code available.

Interactive SET Language for Windows 95/98/Me/NT/2000/XP: downloads, documentation, bugs, sample problems.

Offers sources, documentation and references to programming language SETL.

SET Language: mathematical programming language closely resembling the language of sets and functions used by Mathematicians. Lets users define sets, then define functions and binary operations on the sets: reference documentation for the library of built-in operations.

A dissertation by David Bacon.

SET Language 2, close relative of SETL, has some clumsy support for closures, an experimental (broken) object system, and redefines integer division to mean something different than in SETL: 3/2 yields 1.5 in SETL, but only 1 in SETL2.