HBrainfuck

My toy implementation of the brainfuck programming language written in Haskell. It does not aim to be as small as possible, being instead written to resresh my Haskell knowledge.

Features

This project aims to be as close to the original brainfuck implementation (in terms of behaviour) as possible. Therefore, it has the following features:

• 8-bit unsigned integer cells with wrapping around (made with Haskell's Word8 type);
• Infinite tape in both directions (instead of a unidirectional 30,000-cell tape in the original);
• The value 10 works as the newline code;
• When an end-of-file is reached upon execution of ,, the value of the current cell is left unchanged.

Additional features and implementation details:

• Interactive mode (activated when the executable is run without a target file). Tape state persists between commands. An interactive session can be ended by inputting EOF;
• Comments are supported;
• Optimized cell increments and decrements, [-], [+];
• When there is a ] in the code without preceding [, a parse error is raised.

Running

The code from this project can be run with cabal:

$ cabal run brainfuck

or by manually compiling it with GHC (the contents of /src must be in your current directory):

$ ghc Main.hs

To actually run the compiled executable use

> Main.exe <script>
> Main.exe

on Windows, or

$ ./Main <script>
$ ./Main

on GNU/Linux.

Status

The interpreter is fully functional.