xpath /foo/bar@attr doesn't match the attribute node but the bar element about xpath HOT 6 CLOSED

@mildred , Sorry for the late reply .

I don't think this is a problem. /foo/bar@attr expression means searchs bar element that have a attr name.

The package Expr have two methods: Seelct and Evaluate. if you want matches attr="b", you can consider Evaluate method. #4 (comment)

expr, err := xpath.Compile("//img/@src")
val := expr.Evaluate(nav)
switch typ := val.(type) {
case *xpath.NodeIterator:
    for typ.MoveNext() {
	fmt.Println(typ.Current().Value()) // output @src value
    }
}

from xpath.

Thank you, but the test I made here uses Evaluate and not Select, but the result is not the attribute node but the element. Am I missing something?

from xpath.

The /foo/bar@attr change to /foo/bar/@attr, I think expression /foo/bar@attr and /foo/bar/@attr is different results.

expr, _ := xpath.Compile("//foo/bar/@attr")
iter := expr.Evaluate(xmlquery.CreateXPathNavigator(doc))
switch typ := iter.(type) {
case *xpath.NodeIterator:
	for typ.MoveNext() {
		fmt.Printf("%v:%s\n", typ.Current().NodeType(), typ.Current().LocalName())
	}
}

from xpath.

Good to know. Then the question is which behaviour confirms with the XPath W3C recommendation. Do you have a goal to follow the recommendation closely or not?

When looking through the recommendation, the only occurence of node/@attr is for ../@attr. It seems for non parent elements, they use elem@attr directly.

from xpath.

I'm test foo/bar@attr expression on xpath-tester, got parse error:
Unable to parse any XML input. Unexpected token "@" beyond end of expression

This error also occurs on .NET when using XML library.

So the elem@attr looks is not correct syntax. xpath package should be return error when parsing this expression, but it not.

from xpath.

You are completely right, and I apologize for the issue that is not an issue. I tested this expression somewhere and I assumed that because it worked there, it was valid XPath.

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