class Array

def from(position)

%w( a b c ).from(-10) # => []
%w( a b c d ).from(-2) # => ["c", "d"]
%w().from(0) # => []
%w( a b c d ).from(10) # => []
%w( a b c d ).from(2) # => ["c", "d"]
%w( a b c d ).from(0) # => ["a", "b", "c", "d"]

Returns the tail of the array from +position+.
def from(position)
  self[position, length] || []
end