function user_pre_effect(fn) {
	validate_effect('$effect.pre');
	if (DEV) {
		define_property(fn, 'name', {
			value: '$effect.pre'
		});
	}
	return render_effect(fn);
}
Internal representation of `$effect.pre(...)`
@param {() => void | (() => void)} fn
@returns {Effect}