var group = {

    names: []

}

var groupList = {

    group: [],

    activity:[]

}

​

$(document).ready(function(){

    $("#play").click(function(){

        var soccer = group;

        var person = "Jack";

        soccer.names.push(person);

        var person = "Amber";

        soccer.names.push(person)

        groupList.group.push(soccer); //group[0]

        // how do I make a constructor for a new group?

        var soccer1 = jQuery.extend(true,{}, group);

        var person = "Jill";

        soccer1.names.push(person)

        groupList.group.push(soccer1); //group[1]

        // expect group 0 to be [Jack,Amber] (but pushing Jill on group1 updates group0)

        $("#beta").append("Soccer Group: "+groupList.group[0].names +"<br/>");

         // expect group 1 to be either [Jack,Amber,Jill] or [Jill]

        $("#beta").append("Soccer Group: "+groupList.group[1].names +"<br/>");

    });

​

});