Simplified XML?

?sxml version=1.0?
root-element

-- this is a single-line comment.  Single-line comments
an-element attribute1="1.0" attribute2=2.0
child-element attribute3=<=>?!"'&sp;&        |             attribute4="<=>?!"' &"
another-one attribute5="bla" > example text
  > this text is part of the "another one" element
> this text is part of an-element
an-element/ -- closing tag is optional.
          -- if present, the XML reader would use it for error-checking