xml - Unclear use of // in XPath -

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let's @ following xml file:

<a>   <b w="w">     <b1 x="x" />     <b2 y="y" />   </b> </a>

the following xpath query returns elements b1 , b2:

/*/*//*

from conclude //* means select elements descendants of b not including b itself.

however following xpath query returns attributes w, x, y:

/*/*//@*

so conclude //@* means select attributes appear in descendants of b including b itself.

how work? // work differently elements vs attributes, or there i'm missing?

// short /descendant-or-self::node()/

/* meanwhile identifies child nodes current position.

starting root, /*/*// therefore moves <a> (child of root) , <b> (all children of <a> being single <b>) , selects descendant-or-self::node(), say, <b>, <b1> , <b2>.

it's starting point of <b>, <b1> , <b2> matched /*/*// 2 paths differ.

/*/*//* matches child nodes of nodes. since <b1> , <b2> don't have child nodes, matches child nodes of <b>: <b1> , <b2>.

/*/*//@* matches attributes of nodes. since <b>, <b1> , <b2> have attributes, of attributes matched.

from conclude //* means select elements descendants of b not including b itself.

yes, indirectly. means "select elements descendants of b including b itself, , then find children". amounts "all descendants of b not b" went through "including b" there.


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