About function parameters

Let's look at a chestnut first:

function buildUrl() {
    var qs = "?debug=true";

    with(location){
        var url = href + qs;
        console.log(location) ;
    }

    return url;

}

var result = buildUrl();
alert(result);

　

The with statement receives the location object, so its variable object contains all the properties and methods of the location object.