BP is like a slightly messier BrainFuck. Its alphabet size of 17 is rather odd. Its spec (Section E.2 of [1]) says > programs containing unbalanced parentheses

BP is like a slightly messier BrainFuck. Its alphabet size of 17 is rather odd. Its spec (Section E.2 of [1]) says > programs containing unbalanced parentheses are made valid, in particular by skipping any additional ]. But that still leaves programs invalid programs like "[[[[". From a theoretical viewpoint, its biggest flaw is the lack of an input tape, which makes it a non-optimal description method in the sense of [2]. In particular, while BLC programs are at most a constant larger than BP ones, the reverse is not true. The version of BF that I interpret in [3] is still optimally universal, because its program delimiting fist unbalanced ] is followed by its binary input. [1] https://arxiv.org/html/2401.14953v1 https://arxiv.org/html/2401.14953v1 [2] https://gist.github.com/tromp/86b3184f852f65bfb814e3ab0987d861#universality https://gist.github.com/tromp/86b3184f852f65bfb814e3ab0987d8... [3] https://gist.github.com/tromp/86b3184f852f65bfb814e3ab0987d861#brainfuck https://gist.github.com/tromp/86b3184f852f65bfb814e3ab0987d8...