brainfoose

========== Brainfoose

A brainfuck REPL.

Installation

Pypi (recommended):

sudo pip3 install brainfoose

Manual installation using git master:

git clone https://github.com/abactel/brainfoose

cd brainfoose

pip install -r requirements.txt

sudo setup.py install

Usage

Usage: brainfoose [--run_command=<programs>]

``brainfoose [--tape_size=<tape_size>]``

``brainfoose [--verify_program=<tape_size>]``

``brainfoose (-h | --help)``

``brainfoose --version``

Options: -h, --help Show this message --version Show version information --run Run a command without starting a REPL --tape_size=<tape_size> Set size of tape [default: 3000]

The syntax of the language is as follows:

+--------+----------------------------------------------------------------------+ | Token | Meaning | +========+======================================================================+ | ? | Print a help screen | +--------+----------------------------------------------------------------------+ | > | Increment the data pointer by 1. | +--------+----------------------------------------------------------------------+ | < | Decrement the data pointer by 1. | +--------+----------------------------------------------------------------------+ | + | Increment the value at the data pointer by 1. | +--------+----------------------------------------------------------------------+ | - | Decrement the value at the data pointer by 1. | +--------+----------------------------------------------------------------------+ | . | Output the byte at the data pointer. The byte is formatted to the | | | character it represents. | +--------+----------------------------------------------------------------------+ | , | Store a value at the data pointer’s position. The character is | | | as a decimal byte representing the character. The character is | | | accepted form a standard input prompt. | +--------+----------------------------------------------------------------------+ | [ | If the value at the data pointer is 0, move to matching ]. | +--------+----------------------------------------------------------------------+ | ] | If the value at the data pointer is not 0, move to matching [. | +--------+----------------------------------------------------------------------+ | $ | Display tape up to last non-zero cell. | +--------+----------------------------------------------------------------------+ | & | Reset tape. | +--------+----------------------------------------------------------------------+ | % | Load program from file, syntax: %[filename]. | +--------+----------------------------------------------------------------------+

The wikipedia page on brainfuck includes the following tutorial: ::

[ This program prints "Hello World!" and a newline to the screen, its
  length is 106 active command characters. [It is not the shortest.]

  This loop is an "initial comment loop", a simple way of adding a comment
  to a BF program such that you don't have to worry about any command
  characters. Any ".", ",", "+", "-", "<" and ">" characters are simply
  ignored, the "[" and "]" characters just have to be balanced. This
  loop and the commands it contains are ignored because the current cell
  defaults to a value of 0; the 0 value causes this loop to be skipped.
]
++++++++               Set Cell #0 to 8
[
    >++++               Add 4 to Cell #1; this will always set Cell #1 to 4
    [                   as the cell will be cleared by the loop
        >++             Add 2 to Cell #2
        >+++            Add 3 to Cell #3
        >+++            Add 3 to Cell #4
        >+              Add 1 to Cell #5
        <<<<-           Decrement the loop counter in Cell #1
    ]                   Loop till Cell #1 is zero; number of iterations is 4
    >+                  Add 1 to Cell #2
    >+                  Add 1 to Cell #3
    >-                  Subtract 1 from Cell #4
    >>+                 Add 1 to Cell #6
    [<]                 Move back to the first zero cell you find; this will
                        be Cell #1 which was cleared by the previous loop
    <-                  Decrement the loop Counter in Cell #0
]                       Loop till Cell #0 is zero; number of iterations is 8

The result of this is:
Cell No :   0   1   2   3   4s

Further reading

• https://learnxinyminutes.com/docs/brainfuck/
• https://en.wikipedia.org/wiki/Brainfuck
• http://blog.klipse.tech/brainfuck/2016/12/17/brainfuck.html