Public Identifiers

Unlike SGML, which specified a syntax for public identifiers, and a
more-or-less formal interpretation, XML treats them as simple strings, and
suggests only that they may be used "to generate an alternative" URI
reference, where the default is of course contained in the system
identifier.

I am curious about what sorts of things developers are doing with public
identifiers, if anything at all. Are you still using SGML-style formal
public identifiers, out of habit, or necessity? Are there any efforts to
formalize other semantics for the field, for example as a way of specifying
alternative resolution strategies for the system identifier?

// Gregory Murphy <>