Installation:

`meteor add nous:state`

Usage

Template.mytemplate.initState({
  someVar: 'default value',
  selectedColor: undefined
});
  
Template.mytemplate.helpers({
  getCar: function () {
    color = Template.instance().vars.selectedColor;
    return Cars.findOne({country: @country, color: color});
  }
});

Template.mytemlpate.events({
  'click .selectColor': function (e, tpl) {
    tpl.vars.selectedColor = e.target.value;
  }
});

or you can use our methods and CoffeScript for more beatifull code:

Template.mytemplate.initState
  someVar: 'default value'
  selectedColor: undefined
  
Template.mytemplate.methods
  getCar: ->
    Cars.findOne
      country: @context.country
      color: @vars.selectedColor})

Template.mytemlpate.events
  'click .selectColor': (e, tpl) ->
    tpl.vars.selectedColor = e.target.value

Persistence and Hooks

If you want to store/restore to/from database, you can use onStateUpdated and onStateRequested template hooks. Also you can use nous:tabmanager if you want to persist your state (all tree) into database each time URL is changed, to have possibility to restore it when you back.