How to split a list into equal sized lists in Groovy?

Question

If I have this:

def array = [1,2,3,4,5,6]

Is there some built-in which allows me to do this ( or something similar ):

array.split(2)

and get:

[[1,2],[3,4],[5,6]]

?

Answer 1

EDIT As of groovy 1.8.6 you can use the collate method on lists

def origList = [1, 2, 3, 4, 5, 6, 7, 8, 9]
assert [[1, 2, 3, 4], [5, 6, 7, 8], [9]] == origList.collate(4)

---

Another method using inject and metaClasses

List.metaClass.partition = { size ->
  def rslt = delegate.inject( [ [] ] ) { ret, elem ->
    ( ret.last() << elem ).size() >= size ? ret << [] : ret
  }
  if( rslt.last()?.size() == 0 ) rslt.pop()
  rslt
}

def origList = [1, 2, 3, 4, 5, 6]

assert [ [1], [2], [3], [4], [5], [6] ] == origList.partition(1)
assert [ [1, 2], [3, 4], [5, 6] ]       == origList.partition(2)
assert [ [1, 2, 3], [4, 5, 6] ]         == origList.partition(3)
assert [ [1, 2, 3, 4], [5, 6] ]         == origList.partition(4)
assert [ [1, 2, 3, 4, 5], [6] ]         == origList.partition(5)
assert [ [1, 2, 3, 4, 5, 6] ]           == origList.partition(6)
assert [ ]                              == [ ].partition(2)

Edit: fixed an issue with the empty list