Probem with tab space when insert a new XML element

Hi, I am new in editing xml and I have met this problem: I edit xml files using lua commands and when I replace or add a new xml row, next row's tab space (or one empty space character) is disappeared. It is something like:
Moreover, in the case of a replacement, if there was a comment in that line, it goes in next line alone:
This is rather a cosmetic problem and does not actually affect the structure of the xml but if there are many such changes I cannot read easily the xml any more and search for other potential mistakes. I tried adding page breaks and such with no luck so far. Is there a solution?

Thanks!

What's your code to insert into the XML? If you're doing it manually then you need to copy whitespace from the next node. Unless it's a closing tag, then you need to add one more level of indentation.

For example,

The addition or replacement is happened automatically by a Lua command. Since this command must be in one line what I have to add before or/and after "<c>" so I can have the result (the red spaces) in <d> element? Because the problem appears in the very next line (<d> in your example) and not in the one I add (<c> in your example).

Which would be...?

XML.InsertXML("a/b", "<c>", XML.AFTER);

or if I want <c> to replace <b> it should be:

XML.InsertXML("a/b", "<c>", XML.REPLACE);

It doesn't seem like there's any way to fix the indentation in Lua. At least not according to the documentation.

A few editors have a Reformat Document-type action, and most XML viewers will present the markup reformatted for you to see...

O.K. I thought that it was something I didn't know about it..

Thanks a lot Requinix for your hep.