bnbf - the bignum brainfuck interpreter

bnbf is a brainfuck interpreter featuring bignum memory cells and many runtime options.

There is a git repository at http://github.com/jes/bnbf which is where new development happens.

1. Compiling
2. Usage
3. Contact

1. Compiling

Before running bnbf you will need to compile it. This is relatively straightforward, simply run
$ make
in the directory containing this file and the Makefile, and bnbf will be compiled. The executable will be the file src/bnbf, relative to the directory containing the Makefile.

After you've compiled bnbf, it will probably be a good idea to run the test cases to make sure everything is in order. To do this, run
$ make test
and ensure that there are 0 failures.

Having compiled and tested bnbf, you may want to install it. If you are the root user, running
$ make install
will do this for you, otherwise just copy src/bnbf to somewhere in your path (for example, ~/bin). There is also a man page in the file bnbf.1 which you can put somewhere in your MANPATH.

2. Usage

The man page is the place you should go to for help, but running
$ bnbf --help
or
$ bnbf --usage
will probably tell you all you need to know. The general method of running bnbf is, for example
$ bnbf --char-io ~/brainfuck/hello_world
if you have a program in ~/brainfuck/hello_world which needs to output characters. As bnbf was designed with numeric computation in mind, the default is for I/O to be numeric instead of character-based.

If you wish to emulate the byte-array memory of other implementations, you can pass the --wrap option, which will cause cell values to wrap back to 0 when incrementing 255, and to wrap up to 255 when decrementing 0. This is no longer implemented using bignum, so there is a fairly significant (roughly 10x) performance advantage to using --wrap where possible or appropriate.

With --wrap enabled, bnbf is currently about 30% slower than the beef interpreter available from http://kiyuko.org/software/beef. I suspect this is because there are a lot of places where bnbf tests whetherthe flag for the --wrap option is set, whereas beef does not support bignum cells, so it knows always to use byte-array memory.

3. Contact

If you find a bug or just want to contact me for any reason, send an email to
James Stanley james@incoherency.co.uk
or find me on IRC as the user jamesstanley on irc.freenode.net. I am usually in the channel #maximilian, so you'll probably find me in there.