Is it possible in XML to have an attribute with a namespace earlier than XMLNS?

Question

Programming

The question is. How possible is such code in XML?

<a:tag a:attr="value" xmlns:a="http://example.com/" />

Parsing such XML is very difficult to program, subtle errors are possible, and even more so if high performance is needed.

Answer 1

Again, you have to answer yourself. Available.
www.oracle.com/technetwork/articles/srivastava-nam...

<?xml version="1.0"?>
<Book isbn="1234"
      pfx:cover="hard"
      xmlns="http://www.library.com"
      xmlns:pfx="http://www.library.com">
  <Title>Sherlock Holmes</Title>
  <Author>Arthur Conan Doyle</Author>
</Book>