OK, good point. Problem is that only the w is still unused as a modifier. And I am not sure the slip-pieces are the all-important application that deserves to use it. We are really running into a fundamental limitation of XBetza, namely that the entire move must be expressible with a single atom. Stride-halving (as in a ski-slider) is still relatively easy through including a dummy initial leg. But stride doubling would require indefinite repetition of a pair of steps of the initial atom, and there is as yet no provision for that. The natural way to do that would be to enclose the part of the description that can be repeated in parentheses (possibly followed by a number to specify a maximum number of repeats). For the Slip-Bishop that would give (afmpaf)F. This notation could also handle pieces like Mao-riders. Or circular / zig-zag riders. So it is a potentially very powerful device. But it is rather cryptic.
Capitals for new atoms are still in more abundant supply. We could do S for Slip-Bishop, and P for Slip-Rook ('Panda'). OTOH, we could also overload another modifier. E.g. q in the sense of circular doesn't seem meaningfull on slider atoms. So qB, qR and qQ could be Slip-Bishop, Slip-Rook and Slip-Queen.
OK, good point. Problem is that only the w is still unused as a modifier. And I am not sure the slip-pieces are the all-important application that deserves to use it. We are really running into a fundamental limitation of XBetza, namely that the entire move must be expressible with a single atom. Stride-halving (as in a ski-slider) is still relatively easy through including a dummy initial leg. But stride doubling would require indefinite repetition of a pair of steps of the initial atom, and there is as yet no provision for that. The natural way to do that would be to enclose the part of the description that can be repeated in parentheses (possibly followed by a number to specify a maximum number of repeats). For the Slip-Bishop that would give (afmpaf)F. This notation could also handle pieces like Mao-riders. Or circular / zig-zag riders. So it is a potentially very powerful device. But it is rather cryptic.
Capitals for new atoms are still in more abundant supply. We could do S for Slip-Bishop, and P for Slip-Rook ('Panda'). OTOH, we could also overload another modifier. E.g. q in the sense of circular doesn't seem meaningfull on slider atoms. So qB, qR and qQ could be Slip-Bishop, Slip-Rook and Slip-Queen.