How could I add a parent to a node?

[stereomatchingkiss]

Original xml

<?xml version="1.0"?>
<measure>
     <layer>
         <A1>SomeValue</A1>
    </layer>
</measure>

The xml output I want

<?xml version="1.0"?>
<measure>
     <staff>
         <layer>
             <A1>SomeValue</A1>
        </layer>
    </staff>
</measure>

I can append as a child under measure by append_child, but how could I make every elements under measure as the child of ? Thanks

[zeux]

append_child + append_move for all other children of measure; see https://pugixml.org/docs/manual.html#modify.move

Note that you will need to be careful about iterating, as append_move changes the sibling structure; you could do something like

pugi::xml_node staff = measure.append_child("staff");
while (measure.first_child() != staff)
    staff.append_move(measure.first_child());

[stereomatchingkiss]

append_child + append_move for all other children of measure; see https://pugixml.org/docs/manual.html#modify.move

Note that you will need to be careful about iterating, as append_move changes the sibling structure; you could do something like

pugi::xml_node staff = measure.append_child("staff");
while (measure.first_child() != staff)
    staff.append_move(measure.first_child());

Thanks, it works, I have another question

Original xml

<?xml version="1.0"?>
<measure>
     <layer>
         <A1>SomeValue</A1>
    </layer>
    <rend xml:id="rhwp5l2" halign="left">pp</rend>
</measure>

pugi::xml_node staff = measure.append_child("staff");
while (measure.first_child() != staff)
    staff.append_move(measure.first_child());

First solution would make the node become the parent of layer and rend, how could I make it become parent of layer only?

<?xml version="1.0"?>
<measure>
     <staff>
         <layer>
             <A1>SomeValue</A1>
        </layer>
    </staff>
    <rend xml:id="rhwp5l2" halign="left">pp</rend>
</measure>

Tried

 auto mnode = mei_mnode.node();
 if(auto const cname = string(mnode.name()); cname != "staff"){
     if(auto lnode = mnode.child("layer")){ 
         cout<<"cname != staff, cname == "<<cname<<endl;
          xml_node staff_node = mei_mnode.node().prepend_child();
          staff_node.set_name("staff");
                 
          while(lnode.parent() != staff_node)
               staff_node.prepend_move(lnode.first_child());
      }
 }

But this cause infinite loop

[stereomatchingkiss]

Fix the bug, just change

xml_node staff_node = mei_mnode.node().prepend_child();

to

xml_node staff_node = mei_mnode.node().append_child();