Confusion on XPath Grammar concerning attribute axis

Hi,

I wonder what this expression means:

(1) /foo/@attr/bar

or what this one here means:

(2) /foo/@text()

ad (1):
This expression seems to be perfectly within the range of the grammar, but I cannot understand what it means. Well /foo/@attr takes me to the attribute "attr" of node "foo". But what does /bar do on this context?

ad(2):
Well this looks like a text() test on the attribute axis of foo. But what is the meaning of that?



Thanks for any answers and hints!
Cheers,
Daniel