for...of

Iterates lazily in row-major order (top to bottom, left to right) over all matching cells in a quadrille. Each iteration yields a cell object of the form { row, col, value }. This pattern mirrors JavaScript’s for...of, which is used to loop over iterable objects like arrays and generators.

To yield only a subset of cells, use the cells(filter) method within the loop. The visit(callback, filter?) method offers a concise alternative by applying a callback function to each yielded cell.

Example: Filtering by Value Collection #

(click on canvas to randomize q)

code

Quadrille.cellLength = 50;
let q, hint;

const monkeys = ['🙈', '🙉', '🙊', '🦧'];
const birds = ['🐍', '🦜', '🦚', '🐤'];
const emojis = [...monkeys, ...birds, '🐸', '🐯', '🐱', '🐶', '🐮'];

function setup() {
  createCanvas(8 * Quadrille.cellLength, 8 * Quadrille.cellLength);
  highlight();
}

function draw() {
  background('#DAF7A6');
  drawQuadrille(q);
  drawQuadrille(hint);
}

function mousePressed() {
  highlight();
}

function highlight() {
  q = createQuadrille(8, 8);
  for (const { row, col } of q) {
    q.fill(row, col, random(emojis));
  }
  hint = createQuadrille(8, 8);
  for (const { row, col } of q.cells(monkeys)) {
    hint.fill(row, col, color(0, 140));
  }
}

The first loop (for (const { row, col } of q)) iterates all cells to fill them randomly.
The second loop (for (const { row, col } of q.cells(monkeys))) filters cells containing monkey emojis.

Example: Filtering by Predicate (Value) #

(click on canvas to randomize q)

code

Quadrille.cellLength = 50;
let q, hint;

function setup() {
  createCanvas(8 * Quadrille.cellLength, 8 * Quadrille.cellLength);
  highlight();
}

function draw() {
  background('#D6EAF8');
  drawQuadrille(q);
  drawQuadrille(hint);
}

function mousePressed() {
  highlight();
}

function highlight() {
  q = createQuadrille(8, 8).rand(15, '🐸').rand(15, '🐯').rand(15, '🐮');
  hint = createQuadrille(8, 8);
  for (const { row, col } of q.cells(({ value }) => Quadrille.isFilled(value))) {
    hint.fill(row, col, color(0, 140));
  }
}

Example: Filtering by Combined Predicates (Value, Row, Col) #

(move mouse to highlight 🐸 in hovered column; click to randomize q)

code

Quadrille.cellLength = 50;
let q, hint;

function setup() {
  createCanvas(8 * Quadrille.cellLength, 8 * Quadrille.cellLength);
  q = createQuadrille(8, 8).rand(15, '🐸').rand(15, '🐯').rand(15, '🐮');
  highlight();
}

function draw() {
  background('#D7BDE2');
  drawQuadrille(q);
  drawQuadrille(hint);
}

function mousePressed() {
  q.randomize();
  highlight();
}

function mouseMoved() {
  highlight();
}

function highlight() {
  hint = createQuadrille(8, 8);
  for (const { row, col } of q.cells(({ value, col }) => value === '🐸' && col === q.mouseCol)) {
    hint.fill(row, col, color(0, 140));
  }
}

Syntax #

for (const cell of q)
for (const cell of q.cells(filter))
for (const { row, col, value } of q)
for (const { row, col, value } of q.cells(filter))

Parameters #

Param	Description
`filter`	Optional filter to restrict cells visited. Can be: A value collection (`Array` or `Set`) A predicate function (`({ row, col, value }) => boolean`) If omitted, all cells are included