Golo provides a "for each" style of iteration over iterable elements. Any object that is an instance of java.lang.Iterable can be used in foreach loops, as in:

function concat_to_string = |iterable| {
  var result = ""
  foreach item in iterable {
    result = result + item
  }
  return result
}

In this example, item is a variable within the foreach loop scope, and iterable is an object that is expected to be iterable.

You may use parenthesis around a foreach expression, so foreach (foo in bar) is equivalent to foreach foo in bar.