Need an AddElement method

[suntong]

I need a way to add an etree Element under another etree Element.

Trying to explain in code:

doc := etree.NewDocument()
doc.ReadFromFile("bookstore.xml")
root := doc.SelectElement("bookstore")

Now the root is an etree Element under which are a bunch of <book> XML Elements.

Suppose now I have

docMore.ReadFromString(xmlMoreBooks)

The question is how can I add docMore as new entries under the root etree Element?

I think such feature would be needed by others as well. Please consider adding it.

Thanks

[beevik]

I created a new branch with this change. Here is the associated pull request (PR #18).

Please try it out and let me know if it does what you need.

[suntong]

Thanks a lot Brett!

Could you create a temp tag so that I can pull it from gopkg.in?
Ref http://suntong.github.io/blogs/2016/02/26/godoc-from-branch-code/ for details if you want.

Update, I took a look at the code, and I totally like your new changes. If you create a temp tag, I can do go get from gopkg.in, so as to test the new code on my end.

Thanks

[beevik]

It's already got a tag: v0

[suntong]

sorry, didn't know that. will try this evening...

[suntong]

Yep, that's exactly what I was hoping for. Thanks!

[suntong]

If element el was already the child of another element, it is removed from its current parent element first

You meant, "If element el was already the child of another element under the same root, it is removed from its current parent element first", right?

I meant,

// To add all book nodes under docA to root
for _, e := range docA.FindElements(".//book") {
    // add (e) under root
    root.AddElement(e)
}

After this loop, the docA will stay the same, without any node being removed, right? provided that docA and root are not under the same root.

[beevik]

In that code, docA would be modified, since an element cannot be in two different trees.

To keep docA from being modified, you should do root.AddElement(e.Copy()) instead.

[suntong]

well, actually I hope not. Check this out,
https://github.com/suntong/lang/blob/master/lang/Go/src/xml/et_example.go#L111

docA is in fact untouched, which I think should be the case.

[beevik]

Found the bug. Please see the pull request. (I'll be adding all comments to the PR from now on.)

[suntong]

Gotya. I'm all good now.

[suntong]

Hi Brett,

Would you take a look at https://github.com/suntong/lang/blob/master/lang/Go/src/xml/et_example.go please?

That's the code I tested the above feature and fix, and was good with the tag v0 by then. However, it is not working now. I had been checking your commit log trying to figure out what has changed, but wasn't able to figure out myself.

Thanks