| 12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152 | /** * Returns whether the element is hidden. * @param $elem */export function isHidden($elem) {    return $elem.hasAttribute("hidden")        || ($elem.hasAttribute("aria-hidden") && $elem.getAttribute("aria-hidden") !== "false")        // A quick and dirty way to check whether the element is hidden.        // For a more fine-grained check we could use "window.getComputedStyle" but we don't because of bad performance.        // If the element has visibility set to "hidden" or "collapse", display set to "none" or opacity set to "0" through CSS        // we won't be able to catch it here. We accept it due to the huge performance benefits.        || $elem.style.display === `none`        || $elem.style.opacity === `0`        || $elem.style.visibility === `hidden`        || $elem.style.visibility === `collapse`;    // If offsetParent is null we can assume that the element is hidden    // https://stackoverflow.com/questions/306305/what-would-make-offsetparent-null    //|| $elem.offsetParent == null;}/** * Returns whether the element is disabled. * @param $elem */export function isDisabled($elem) {    return $elem.hasAttribute("disabled")        || ($elem.hasAttribute("aria-disabled") && $elem.getAttribute("aria-disabled") !== "false");}/** * Determines whether an element is focusable. * Read more here: https://stackoverflow.com/questions/1599660/which-html-elements-can-receive-focus/1600194#1600194 * Or here: https://stackoverflow.com/questions/18261595/how-to-check-if-a-dom-element-is-focusable * @param $elem */export function isFocusable($elem) {    // Discard elements that are removed from the tab order.    if ($elem.getAttribute("tabindex") === "-1" || isHidden($elem) || isDisabled($elem)) {        return false;    }    return (    // At this point we know that the element can have focus (eg. won't be -1) if the tabindex attribute exists    $elem.hasAttribute("tabindex")        // Anchor tags or area tags with a href set        || ($elem instanceof HTMLAnchorElement || $elem instanceof HTMLAreaElement) && $elem.hasAttribute("href")        // Form elements which are not disabled        || ($elem instanceof HTMLButtonElement            || $elem instanceof HTMLInputElement            || $elem instanceof HTMLTextAreaElement            || $elem instanceof HTMLSelectElement)        // IFrames        || $elem instanceof HTMLIFrameElement);}//# sourceMappingURL=focusable.js.map
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