Deep exclusions

From W3C Wiki

Deep exclusions (a co-constraint use case)

Make the legality of a particular element type depend on the absence of another element type from the stack.

source: XHTML


Other use cases: Co-constraint Use Cases

Description

   <a> elements cannot appear, at any depth, within other <a> elements.

Analysis

(Add your analysis here; see your name in pixels!)

Possible solutions

Relax NG

Schematron

Check clause

SchemaPath

Conditional Type