def md_el(node_type, children=[], meta={}, al=nil)
		if  (e=children.first).kind_of?(MDElement) and 
			e.node_type == :ial then
			if al
				al += e.ial
			else
				al = e.ial
			end
			children.shift
		end 
		e = MDElement.new(node_type, children, meta, al)
		e.doc = @doc
		return e
	end
def md_el(node_type, children=[], meta={}, al=nil)
		if  (e=children.first).kind_of?(MDElement) and 
			e.node_type == :ial then
			if al
				al += e.ial
			else
				al = e.ial
			end
			children.shift
		end 
		e = MDElement.new(node_type, children, meta, al)
		e.doc = @doc
		return e
	end
if the first is a md_ial, it is used as such