It might also be worth to mention where character doubling can be used to slightly alter the meaning. Directional modifiers can generally be doubled to prevent they would be combined with a perpendicular one for indicating an in-between direction. In addition oo = toroidal wrapping, nn = non-jumping and generating e.p. rights on the squares passed through, ii = only on the squares where such a piece started. And proposed cc = rifle capture as automatic side effect when there is something to capture there.
So unassigned capitals currently are E, M, P, S, T, V. Perhaps P would be a useful shorthand for the Pawn move, which has a bit of a lengthy description in basic XBetza. E.g. P3 could be taken to mean fmWfceFifmnW3, a Pawn that can step up to 3 forward initially.
The only unassigned lower case are t and w. Betza used t as 'then' in a kind of bracket notation, but this seemed redundant, as the brackets already imply it. At this point he was abandoning his original goal of only using alphanumeric characters in the notation by allowing the brackets, but was still too much leaning towards the old ways to accept punctuation in general.
I coined the idea of using M (mirror) for pieces like the Ultima Chameleon, which much borrow the move set of their victim to capture. And to use E in the bracket notation (where each leg can use a different atom) as a test for whether you are on an edge square without moving.
K = WF, not AF.
It might also be worth to mention where character doubling can be used to slightly alter the meaning. Directional modifiers can generally be doubled to prevent they would be combined with a perpendicular one for indicating an in-between direction. In addition oo = toroidal wrapping, nn = non-jumping and generating e.p. rights on the squares passed through, ii = only on the squares where such a piece started. And proposed cc = rifle capture as automatic side effect when there is something to capture there.
So unassigned capitals currently are E, M, P, S, T, V. Perhaps P would be a useful shorthand for the Pawn move, which has a bit of a lengthy description in basic XBetza. E.g. P3 could be taken to mean fmWfceFifmnW3, a Pawn that can step up to 3 forward initially.
The only unassigned lower case are t and w. Betza used t as 'then' in a kind of bracket notation, but this seemed redundant, as the brackets already imply it. At this point he was abandoning his original goal of only using alphanumeric characters in the notation by allowing the brackets, but was still too much leaning towards the old ways to accept punctuation in general.
I coined the idea of using M (mirror) for pieces like the Ultima Chameleon, which much borrow the move set of their victim to capture. And to use E in the bracket notation (where each leg can use a different atom) as a test for whether you are on an edge square without moving.