[log in to unmask]: wrote

You want your XML files spell-checked? You could
write an application which did a callout to a
spell-checker for each text node.

Sure, but this wasn't the question.

[log in to unmask] wrote:

> PS: Instead of explaining NDR. - my English is too poor for this - I would a=
> sk how I can say to a standard XML parser: "Check the nodes with attribution=
>  of OSE for well-formedness!" (Old Spelling English ;-)

This is an impossible request. Before the parser can determine that a
node exists, let alone what its attribute values might be,  the document
must be entirely well formed.
Well-formedness is a precondition for a parser to operate on a document
in any way.

Obviously I have to sharpen my terminology. You too?
If 'well-formedness' in the given TEI context is to discuss only on the level of metalanguage, nodes are not to 'validate' (= parsed against the grammar defined by DTD or otherwise). But what means then the passage rightly picked up by Sylvain?

[log in to unmask] wrote:

A strange statement in the Guidelines:

    By default, a <formula> is assumed to contain character data which
is not validated in any way:   

Underlining the strangeness of such remark I cite an example for a date structure element:

_dateStruct value='26-10-1775'_ _day value='26'_26_/day_ _month
value='10'_October_/month_ _year value='1775'_1775_/year_ _/dateStruct_

For me such examples are showing how TEI conformant markup allows semantic document processing without looking inside the nodes. Isn't it?