> <\body> For compatibility reasons with the XML technology, also supports the serialization of documents in the XML format. However, the XML format is generally more verbose and less readable than the default format. In order to save or load a file in the XML format (using the extension), you may use .\ It should be noticed that documents do not match a predefined DTD, since the appropriate DTD for a document depends on its style. The XML format therefore merely provides an XML representation for trees. The syntax has both been designed to be close to the tree structure and use conventional notations which are well supported by standard tools. The leafs of trees are translated from the universal encoding into Unicode. Characters without Unicode equivalents are represented as entities (in the future, we rather plan to create a tag for representing such characters). Trees with a single child are simply represented by the corresponding XML tag. In the case when a tree has several children, then each child is enclosed into a tag. For instance, > is simply represented as <\quote-env> sqrt\y+z\/sqrt\>> whereas the fraction > is represented as <\quote-env> <\framed-fragment> <\with|par-par-sep|0fn> <\verbatim> \frac\ \ \ \tm-arg\1\/tm-arg\ \ \ \tm-arg\2\/tm-arg\ \/frac\ In the above example, the whitespace is ignored. Whitespace may be preserved by setting the standard attribute to . Some tags are represented in a special way in XML. The tag is simply represented by a textual concatenation. For instance, +> is represented as <\quote-env> \frac\\tm-arg\1\/tm-arg\\tm-arg\2\/tm-arg\\/frac\+\sqrt\y+z\/sqrt\ > The tag is not explicitly exported. Instead, each paragraph argument is enclosed within a tag. For instance, the quotation <\quote-env> <\dutch> Ik ben de blauwbilgorgel. Als ik niet wok of worgel, is represented as <\tm-fragment> <\verbatim> \quote-env\ \ \ \tm-par\ \ \ \ \ Ik ben de blauwbilgorgel. \ \ \/tm-par\ \ \ \tm-par\ \ \ \ \ Als ik niet wok of worgel, \ \ \/tm-par\ \/quote-env\ A tag with only string attributes and values is represented using the standard XML attribute notation. For instance, \Psome text\Q would be represented as <\quote-env> some \with color="blue"\blue\/with\ text > Conversely, provides the primitive in order to represent attributes of XML tags. For instance, the XML fragment <\quote-env> some \mytag beast="heary"\special\/mytag\ text > would be imported as \P|special> text>\Q. This will make it possible, in principle, to use as an editor of general XML files. >