Empty text childs increase XML file size

[Mai1er]

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// (pseudo code) xml::node Node = ParentNode.append_child("NewChildNode"); Node.text().set(""); // << create new text-type subchild with no text

// after save document to file we have: <NewChildNode></NewChildNode> // but must be (by default output format) <NewChildNode /> // "virtual" empty text-child lock short form of record

[zeux]

Sure... why is this a problem? It's not clear to me if changing this is worth the benefit, as the application can just not create empty text children.

[Mai1er]

I have text fields assigned by a template, without checking for empty/filled. There are many fields in the file and often most of them are empty. This increases the size of the files by 20-30%, and there are... a lot of files on the disk.

Besides, why leave a mistake when you can do better?

[zeux]

Ok, and it's impractical for your application to check if the field is empty before assigning? What if the field value is purely white space?

Additionally, if your data has a lot of empty fields and the output size matters, do you need to add the nodes corresponding to empty fields at all? <NewChildNode /> still takes space and you might be able to omit the node entirely.

Overall I'm not entirely sure where the "mistake" is here. Maybe set() shouldn't even create a PCDATA node, or maybe the library works fine; it's an odd corner case.

[Mai1er]

1. THATS not app side of responsibility
2. empty fields need by format

[chr-thien]

This behavior is confusing because:

1. you create a XML file with empty nodes -> after save with default flags then empty nodes are expanded.
2. you load that file and save it again with default flags -> empty nodes got compressed.

I found out after comparing files with diff tool. It is impractical to compare those files using a diff tool.

So in case one wants to have expanded empty nodes then one should use existing format flag format_no_empty_element_tags. Omitting that flag one would always expect compressed empty nodes.