visit(callback, filter?)

A syntactic sugar for the for...of loop. Internally defined as:

visit(callback, filter) {
  for (const cell of this.cells(filter)) {
    callback(cell);
  }
}

It simplifies iteration over cells by calling callback on each { row, col, value } cell object. Ideal for concise arrow functions and inline operations.

Use for...of instead if you need to break early from the loop.

Example #

(move mouse to highlight 🐸 filled cells in the hovered col, and 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);
  q.visit(
    ({ row, col }) => hint.fill(row, col, color(0, 140)),
    ({ value, col }) => value === '🐸' && col === q.mouseCol
  );
}

This example is a direct adaptation of the corresponding for...of example. Additional examples from the for...of section can be rewritten using visit following the same pattern.

Syntax #

visit(callback, filter?)

Parameters #

Param	Description
`callback`	Function to execute on each matching cell. Receives a `{ row, col, value }` object as argument
`filter`	Optional filter to restrict cells visited. It can be: a value collection (`Array` or `Set`) a predicate function (`({ row, col, value }) => boolean`) If omitted, all cells are included