May even this would be clearer:

```coffee
setTabStopIndex: (@tabStopIndex) ->
  @settingTabStop = true
  markerSelected = false

  selections = []
  for marker in @tabStopMarkers[@tabStopIndex] when marker.isValid()
    selections.push(marker.getBufferRange())

  if selections.length > 0
    @editor.setSelectedBufferRanges(selections)
    markerSelected = true

  @settingTabStop = false
  markerSelected
```