Valid PI tag names

[Spacen Jasset]

I am thinking of using XML PI tags to convey some preprocessing
instructions to a pre-processor before passing the xml to an xmlparser
in an external library.

Something likethis

<?pi?>

I've read the xml specification and it seems to allow colons in the PI
name like namespaces, thus:

<?pi:test?>

However, internet exporer complains the document isn't valid. So
presumably it's not and there is some footnote to this affect somewhere?

 

[Martin Honnen]

Spacen Jasset wrote:

I've read the xml specification and it seems to allow colons in the PI
name like namespaces, thus:

<?pi:test?>

However, internet exporer complains the document isn't valid. So
presumably it's not and there is some footnote to this affect somewhere?

Yes, XML 1.0 doesn't know about namespaces, a second recommendation
covers that and it says in here
<http://www.w3.org/TR/REC-xml-names/#Conformance>

"No entity names, PI targets, or notation names contain any colons."

 

[Richard Tobin]

I've read the xml specification and it seems to allow colons in the PI
name like namespaces, thus:

<?pi:test?>

However, internet exporer complains the document isn't valid. So
presumably it's not and there is some footnote to this affect somewhere?

It's legal XML, but most tools expect conformance to other standards
too, in particular the XML Namespaces specification. This uses colons
for its own purposes, and does not allow them in PI names, so it would
be very unwise to use them. You can still use hyphens and underscores.

-- Richard