Function create_effect

packages/svelte/src/internal/client/reactivity/effects.js:86–179

* @param {number} type * @param {null | (() => void | (() => void))} fn * @returns {Effect}

(type, fn)

 * @returns {Effect}
 */
function create_effect(type, fn) {
	var parent = active_effect;

	if (DEV) {
		// Ensure the parent is never an inspect effect
		while (parent !== null && (parent.f & EAGER_EFFECT) !== 0) {
			parent = parent.parent;
		}
	}

	if (parent !== null && (parent.f & INERT) !== 0) {
		type |= INERT;
	}

	/** @type {Effect} */
	var effect = {
		ctx: component_context,
		deps: null,
		nodes: null,
		f: type | DIRTY | CONNECTED,
		first: null,
		fn,
		last: null,
		next: null,
		parent,
		b: parent && parent.b,
		prev: null,
		teardown: null,
		wv: 0,
		ac: null
	};

	if (DEV) {
		effect.component_function = dev_current_component_function;
	}

	current_batch?.register_created_effect(effect);

	/** @type {Effect | null} */
	var e = effect;

	if ((type & EFFECT) !== 0) {
		if (collected_effects !== null) {
			// created during traversal — collect and run afterwards
			collected_effects.push(effect);
		} else {
			// schedule for later
			Batch.ensure().schedule(effect);
		}
	} else if (fn !== null) {
		try {
			update_effect(effect);
		} catch (e) {
			destroy_effect(effect);
			throw e;
		}

		// if an effect doesn't need to be kept in the tree (because it