cells(filter?)

Generator function that lazily yields matching cells in the quadrille, each as an object of the form { row, col, value }.

Traversal is row-major (top to bottom, left to right). Returns an IterableIterator—not an array—so values are produced on demand.

Examples

No filter: yield all cells

q.cells();

Function filter: test value only

q.cells(value => value != null);

Use Quadrille.isFilled, Quadrille.isEmpty, or a custom predicate.

Array / Set filter: whitelist of values

q.cells(['a', 'b', 'c']);
q.cells(new Set([1, 2, 3]));

Yields cells whose value is included.

Object filter: combine value, row, and col predicates

q.cells({
  value: v => typeof v === 'string',
  row: r => r % 2 === 0,
  col: c => c < 4
});

Each predicate is optional. All must match if provided.

Advanced: transform or analyze matching cells

// Extract values from filled cells in the top-left 4×4 block
const values = Array.from(q.cells({
  value: Quadrille.isFilled,
  row: r => r < 4,
  col: c => c < 4
})).map(({ value }) => value);

Use this when:

• you need an array of matching cells,
• you’re chaining with array methods like map or reduce,
• or you’re doing offline processing or analysis.

Syntax

cells()
cells(filter)

Parameters