5.3.0, for example, new ol. Control. ZoomSlider (), how do I know the structure of the ZoomSlider method has several? Do you want to preach to participate? This API is completely can't see? There are the following ZoomToExtent, a extend inside, where come of, from the document also can't see it completely

 
Controls: ol. Control. Defaults (). The extend ([
New ol. Control. ZoomSlider (), 
New ol. Control. ZoomToExtent ({
The extend: [
12667718, 2562800, 
12718359, 2597725 
] 
}) 
])