Function files

src/io/files.js:75–2128

(p5, fn)

}

function files(p5, fn){
  /**
   * Loads a JSON file to create an `Object`.
   *
   * JavaScript Object Notation
   * (<a href="https://developer.mozilla.org/en-US/docs/Glossary/JSON" target="_blank">JSON</a>)
   * is a standard format for sending data between applications. The format is
   * based on JavaScript objects which have keys and values. JSON files store
   * data in an object with strings as keys. Values can be strings, numbers,
   * Booleans, arrays, `null`, or other objects.
   *
   * The first parameter, `path`, is a string with the path to the file.
   * Paths to local files should be relative, as in
   * `loadJSON('assets/data.json')`. URLs such as
   * `'https://example.com/data.json'` may be blocked due to browser security.
   * The `path` parameter can also be defined as a [`Request`](https://developer.mozilla.org/en-US/docs/Web/API/Request)
   * object for more advanced usage.
   *
   * The second parameter, `successCallback`, is optional. If a function is
   * passed, as in `loadJSON('assets/data.json', handleData)`, then the
   * `handleData()` function will be called once the data loads. The object
   * created from the JSON data will be passed to `handleData()` as its only argument.
   * The return value of the `handleData()` function will be used as the final return
   * value of `loadJSON('assets/data.json', handleData)`.
   *
   * The third parameter, `failureCallback`, is also optional. If a function is
   * passed, as in `loadJSON('assets/data.json', handleData, handleFailure)`,
   * then the `handleFailure()` function will be called if an error occurs while
   * loading. The `Error` object will be passed to `handleFailure()` as its only
   * argument. The return value of the `handleFailure()` function will be used as the
   * final return value of `loadJSON('assets/data.json', handleData, handleFailure)`.
   *
   * This function returns a `Promise` and should be used in an `async` setup with
   * `await`. See the examples for the usage syntax.
   *
   * @method loadJSON
   * @param  {String|Request} path path of the JSON file to be loaded.
   * @param  {Function} [successCallback] function to call once the data is loaded. Will be passed the object.
   * @param  {Function} [errorCallback] function to call if the data fails to load. Will be passed an `Error` event object.
   * @return {Promise<Object>} object containing the loaded data.
   *
   * @example
   * let myData;
   *
   * async function setup() {
   *   myData = await loadJSON('assets/data.json');
   *   createCanvas(100, 100);
   *
   *   background(200);
   *
   *   // Style the circle.
   *   fill(myData.color);
   *   noStroke();
   *
   *   // Draw the circle.
   *   circle(myData.x, myData.y, myData.d);
   *
   *   describe('A pink circle on a gray background.');