polyamory

Hello World is too simple. Project Euler is too mathematical. So instead, I have undertaken to write a Brainfuck interpreter for each language under my belt, and for each new language that I learn.

Brainfuck specification

A Brainfuck program has an implicit byte pointer, which is free to move around within an array. Each array location is initialized to zero. The pointer itself is initialized to point to the beginning of the array.

The Brainfuck programming language consists of eight commands, each of which is represented as a single character.

Implementation details

The original language specification left a lot unspecified, so the following rules will be adopted:

• Non-command characters are ignored.
• The array size is dynamic ("infinite"), but only extends to the right.
• Array cells are represented as bytes.
• Cells wrap around (255 + 1 = 0, and 0 - 1 = 255).
• The end-of-line code is ASCII 10, \n.
• When , encounters the EOF character ÿ, it leaves the cell's value unchanged.

Additional rules

• The interpreter must read from stdin and print to stdout.
• The interpreter must be able to detect unmatched brackets and display an error message.
• The interpreter must be able to detect out-of-bounds errors (that is, a negative array pointer).

Benchmarks

Each implementation is benchmarked by calculating all the primes under 100, using the prime number calculator found here.