Detecting first and last item inside a Groovy each{} closure

I am using Groovy's handy MarkupBuilder to build an HTML page from various source data.

One thing I am struggling to do nicely is build an HTML table and apply different style classes to the first and last rows. This is probably best illustrated with an example...

table() {
  thead() {
    tr(){
      th('class':'l name', 'name')
      th('class':'type', 'type')
      th('description')
    }
  }
  tbody() {
    // Add a row to the table for each item in myList
    myList.each {
      tr('class' : '????????') {
        td('class':'l name', it.name)
        td('class':'type', it.type)
        td(it.description)
      }
    }
  }   
}

In the section, I would like to set the class of the element to be something different depending whether the current item in myList is the first or the last item.

Is there a nice Groovy-ified way to do this without resorting to something manual to check item indexes against the list size using something like eachWithIndex{}?