Steptype

WHERE A LINE MAY GO NEXT, on one board: the rules of a single step, which the solver, the check, the drawing and the answer's lines all read, so a bridge or a wall means the same thing everywhere.

• Across an open edge (no wall) to the next cell.
• Onto a BRIDGE only to go straight over it: into the cell beyond, the same way on, never turning. Going across uses the bridge's across slot, going down its down slot; the two are crossed by two different lines.
• Into a PORTAL cell, and so out of the other one the same way on: the step is to the cell beyond the far portal, and the line takes both portal cells on the way (through, in the order it passes them). A portal cell itself has no steps and is never where a step ends; where the cell beyond the far portal is blocked, off the board or across a wall, that way into the portal is no step at all.

Imports carry their .ts so the level script can run this under plain node.

import type { Step } from "@johnmorrisdotca/tsunagi";

type Step = {
    to: number;
    over: number;
    across: boolean;
    through: readonly number[];
};

import type { Step } from "@johnmorrisdotca/tsunagi";

const value: Step = {to:1,over:-1,across:true,through:[]};
console.log(value);

{ to: 1, over: -1, across: true, through: [] }