   constructor: (props) ->
     super props
 
+    keyToChar = _.invert BeatmapsetFilter.charToKey
+    @char = keyToChar[@props.name]
+
     @cache = {}
 
 


          a
            key: i
            href: '#'
            className: cssClasses
            value: option.id
            'data-filter-value': option.id


  cast: (value) =>
    BeatmapsetFilter.castFromString[@props.name]?(value) ? value ? null


  href: (option) =>
    i = @cast(option.id)
    newSelection =
      if @props.multiselect
        _(@currentSelection())[if @selected(i) then 'without' else 'concat'](i).sort().join('.')
      else
        if @selected(i) then @props.default else i

    osu.updateQueryString(null, "#{@char}": newSelection)


  select: (e) =>
