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Programming language born from simple Computer Algebra system. Good at pattern matching in tree structures and in strings.
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Bracmat is software for exploration and transformation of uncharted and complex data. Bracmat employs a pattern matching technique that can handle string data (text) as well as structured data (XML, HTML, JSON, algebraic expressions, email, program code, ...).

Over hundred and fifty examples of Bracmat code can be found at

This distribution contains the following directories and files:

  • doc

    • bracmat.html

      The documentation in HTML format, automatically generated from the file 'help'.

    • bracmat-table.html

      The documentation in HTML format, automatically generated from the file 'help' and using an alternative lay-out with tables.

    • CLIN26-poster.pdf

      Poster presented at the 26th Meeting of Computational Linguistics in the Netherlands (CLIN26) in Amsterdam on December 18, 2015.

    • help

      The documentation in Bracmat format. (You have to run Bracmat and issue 'get$help' to see it properly.)

  • epoc

    • bracmat.SIS

      Installation program for Psion 5MX and Ericsson MC218 PDAs. This file is not always up to date.

  • src

    • java

      Java source code for creating a JNI (Java Native Interface) so the Bracmat evaluator can be called from the Java programming language.


        Example program showing how to evaluate a Bracmat expression from within a Java program

      • dk

        • cst


            Java code that loads the Bracmat dynamic library.

    • Python

      Python and Cython source code for creating a Python module 'prythat' so the Bracmat evaluator can be called from the Python programming language

      • build-launch.bat

        Contains two lines. The first line compiles and links the module, the second tests the result.


        Tests the prythat module.

      • prythat.pyx

        Cython source code that interfaces Python with Bracmat and vv.


        Makefile for buidling the module.

    • Makefile

      Builds the standard edition of bracmat, a "safe" version of bracmat, a version for profiling, and a version for code coverage.

    • bracmat.c

      Most of the source code of the program.

    • bracmat.h

      An optional header file, if you want to compile Bracmat as a library.

    • bracmatJS.html

      Bracmat compiled to Javascript using emscripten, embedded in a single HTML-page. Nice for toy scripts, slow.

    • bracmatdll.cpp,

    • bracmatdll.h

      Source and header files that are needed for building the Windows version of a Bracmat JNI, which requires Bracmat to be in a dynamic linked library.

    • bracmatso.c

      Source file that includes bracmat.c after turning off functionality that we don't want in a JNI running in a production system: low level file manipulations, system() calls, and exit() which would bring the application container down.

    • bracmattest.c

      Program source that links with a Bracmat dynamic library. For Linux.


      Linux script to create a Bracmat JNI. This file contains a comment that describes the steps to create a Bracmat JNI for the Windows platform using Visual C++.

    • dk_cst_bracmat.c, dk_cst_bracmat.h

      Source and header files that are needed for building a Bracmat JNI, which requires Bracmat to be in a dynamic linked library.

    • dlltest.cpp, dlltest.h

      Program source that links with a Bracmat dynamic library. For Windows.

    • editbracmatjs.bra

      A Bracmat script that edits the output of the emscripten C-to-Javascript compiler and creates a HTML page containing Javascript embodying Bracmat.

    • emscriptenHowToHTML.bat

      Windows batch file that runs emscripten and does some postprocessing, creating a Javascript version of Bracmat.

    • json.c

      Source code that implements support for reading JSON-files

    • makeJNI.bat

      Batch file for Windows to create a Bracmat JNI. Should work with a number of versions of Microsoft's C-compiler.

    • xml.c

      Source code that implements support for reading XML-files

  • Changelog

    A document describing changes between versions.


    This file.

  • gpl.txt

    The full text of the GNU public licence.


    Detailed explanation of how to use the wizzard project.bra to create a Bracmat program.

  • lex.bra

    Utility to spot unused variables and functions. It also tells you which variables are used outside their lexical scope. (Which is not an error, since Bracmat is dynamically scoped.)

  • pr-xml-utf-8.xml

    XML test file.

  • project.bra

    A tool to initialise a new Bracmat program. Usage: Read this file ( get'"project.bra" ) and answer the questions. The created program stub has a comment, a class for the program and a reread procedure that reads the file, renames the file to a backup and saves it, thereby nicely reformatting the code. (Most comments are lost!) Some editors discover that the file has been changed and propose to reread the file. In this way, the user doesn't need to bother about formatting. Cyclus: edit program, save from editor, reread in Bracmat, reload in editor, edit program.

  • uni.bra

    A utility that generates UNICODE-related tables from UnicodeData.txt ( These tables, which are also found in bracmat.c, have to be updated every few years, when UnicodeData.txt is updated. Conversion between lower and upper casing is based on these tables.

  • valid.bra

    A test suite. Whenever possible, one or more tests are added for every new functionality and every bug fix.


  • To start an interactive session


    • Quit by typing a closing parenthesis after the {?} prompt.
  • To run Bracmat in batch/mode

    bracmat parm1 parm2 ...

    • Bracmat evaluates each parameter, from left to right. When the last parameter is evaluated, bracmat exits.
    • At least the first parameter must be a valid bracmat expression, appropriately quoted and 'escaped' to pass unscathed through the shell's own parameter evaluation mechanism.


You can download Bracmat from GitHub.

mkdir bracmat
cd bracmat
git init
git remote add origin
git pull origin master
cd ..


The Bracmat source code has no other dependencies than what is provided by Standard C. Building bracmat from source is extremely simple, e.g.:

gcc bracmat.c xml.c json.c

You can also use the Makefile, which is in the src directory.

Bracmat has been compiled and run on the following platforms:

  • Windows
    • All versions, compiled with 32 bit VC 6.0 and newer, BCC 5.02, tcc.
    • A 16 bit version existed until version 2.8
    • Bracmat can be compiled to 64 bits. This gives faster multiplication of very large numbers.
  • RISC-OS (Norcroft C ver 3)
  • EPOC 5 (Psion 5mx, Ericsson MC218: gcc)
  • HP-UNIX (gcc, cc)
  • Solaris (gcc)
  • Linux (gcc)
  • MacOS (xcode)

If you have plans to run Bracmat from Python, you need Python and Cython besides a C-compiler. If you want to do this on a Windows platform, you need Visual Studio C++ 2008 (Correct me if there are ways to use other C++ compilers). The software has been tested on Windows 7 and 8.1, both 64 bit platforms, using Cython version 0.22.1 and Python 2.7.3 (default, Apr 10 2012, 23:31:26) [MSC v.1500 32 bit (Intel)] on win32 (or Python 2.7.10 (default, May 23 2015, 09:40:32) [MSC v.1500 32 bit (Intel)] on win32). On Linux ( Ubuntu 14.04.2 LTS 64 bit), the software is tested with Cython version 0.22, Python 2.7.6 (default, Mar 22 2014, 22:59:56) and gcc version 4.8.2. Contact me if you want a compiled module for Windows and do not have the compiler to build it.


The file valid.bra contains enough tests to get in all corners of the source code, except those that lead to a controled exit condition.

For each error correction and for each new or changed feature a test must be added to valid.bra.

The testsuite valid.bra can also be used to find out how things can be programmed, although there is no good way to quickly search for what you are looking for.

usage: start Bracmat in interactve mode and write

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