========================
Expression: //*[lang('en')]
Object is a Node Set :
Set contains 9 nodes:
1  ELEMENT b
    ATTRIBUTE lang
      TEXT
        content=en
2  ELEMENT x
3  ELEMENT x
4  ELEMENT para
    ATTRIBUTE lang
      TEXT
        content=en
5  ELEMENT div
    ATTRIBUTE lang
      TEXT
        content=en
6  ELEMENT para
7  ELEMENT para
    ATTRIBUTE lang
      TEXT
        content=EN
8  ELEMENT para
    ATTRIBUTE lang
      TEXT
        content=en-us
9  ELEMENT para
    ATTRIBUTE lang
      TEXT
        content=EN-US

========================
Expression: //*[lang('en-us')]
Object is a Node Set :
Set contains 2 nodes:
1  ELEMENT para
    ATTRIBUTE lang
      TEXT
        content=en-us
2  ELEMENT para
    ATTRIBUTE lang
      TEXT
        content=EN-US

========================
Expression: //*[lang('en-gb')]
Object is a Node Set :
Set contains 0 nodes:

========================
Expression: //*[lang('fr')]
Object is a Node Set :
Set contains 0 nodes:

========================
Expression: //*[lang('')]
Object is a Node Set :
Set contains 0 nodes: