Scoped Move
For the listed digits and chess move, prohibit either equal digits or consecutive digits in the related cells.
Parameters
| Parameter | Meaning | Default |
|---|---|---|
| move | The chess move connecting the compared cells. | Required. |
| relation | The relationship to enforce: its operation and any required value, for example {"op":"difference","value":1}. | Required. |
| digits | The allowed or required digits, listed explicitly; repeats in the list count where the rule says so. | Required. |
Maths
Class: first-order.
The shared predicates define the notation and every named predicate.
∀a,b∈C: moveRelation(move,a,b) ∧ (D(a)∈digits ∨ D(b)∈digits) → ¬((relation="same" ∧ D(a)=D(b)) ∨ (relation="consecutive" ∧ |D(a)-D(b)|=1))
For every pair at move, forbid equal digits (same) or difference 1 (consecutive) when either endpoint’s digit belongs to digits. bishop includes every distance on a diagonal.
Example
---
format: open-rules
title: Scoped Move example
setter: Example
source: ""
case: ""
library: https://rules.sudoku-sleuth.com/
status: read
---
```rules
sudoku 9x9
scoped-move move "knight" relation "same" digits [1]
```
Satisfies the rule: r1c1=1, r2c3=6. The specified digit does not repeat across a knight move.
Breaks the rule: r1c1=1, r2c3=1. The specified digit repeats across a knight move.