The Pure Programming Language

Pure is a functional programming language based on term rewriting. Its core is actually purely algebraic and purely functional, but the name can also be taken as a recursive acronym for the "Pure Universal Rewriting Engine." Pure has a modern syntax featuring curried function applications, lexical closures and equational definitions with pattern matching, and thus is somewhat similar to languages of the Haskell and ML variety. But Pure is also a very dynamic language, and is more like Lisp in this respect. The interpreter has an LLVM backend to do JIT compilation, hence programs run blazingly fast and interfacing to C modules is easy.

As a language which uses general term rewriting as its underlying computational model (instead of the lambda calculus, which most other functional programming languages are based on), Pure also offers the symbolic evaluation capabilities which you'd expect from such a language. Pure is closely related to the author's Q language and is slated to eventually become its successor, since it offers many new and powerful features and programs run much faster than their Q equivalents. (OTOH, Q still offers many more library modules right now. Most of these will eventually be ported to Pure, but this will take some time.)

Pure is free software distributed under the GNU General Public License V3. The interpreter is known to compile and run without hitches on Linux, OSX and Windows, porting to other POSIX platforms should be a piece of cake.

Pure on the Web

• The SourceForge project page.
• The SVN repository. (The current development sources are in pure/trunk.)
• The downloads. You can find the official Pure source releases there, and a binary MSI package for MS Windows.
• The MacPorts collection includes Ryan Schmidt's OSX port of Pure.
• The Packman project offers Toni Graffy's RPM packages for SUSE Linux.
• The Gentoo ebuild by Álvaro Castro Castilla is available here.
• The mailing list. Join us there to discuss Pure and ask whatever questions you have.
• The wiki. Not much there yet, but you can help with that. ;-)

Documentation and Examples

• The manual in HTML, Windows HTML help and PDF formats.
• The README, INSTALL and NEWS files for the current release.
• Have a look at the hello.pure example to get an idea how Pure programs look like. More examples.

The Grab Bag

• Eddie Rucker's "pure drop of water" images, freely available for use e.g. as desktop icons or website images (thanks, Eddie!): pure-pics.tar.gz.
• Here is some stuff that you may find useful if you want to build Pure on Windows using Mingw: INSTALL-MinGW.txt by Jiri Spitz. Additional required Mingw libraries, dlls and headers: pure-mingw.zip.
• Cyrille Berger's patch for LLVM 2.3 to add PIC support on 64 bit systems: X86JITInfo.cpp.pic.2.3.patch. You'll need this to compile Pure on x86-64 systems.

Author

Albert Gräf <Dr.Graef at t-online.de>
Dept. of Computer Music
Johannes Gutenberg University of Mainz
Germany

© 2008 by Albert Gräf