These rules seem to work:
a) separators and terminators are collectively called 'terminating markup'.
b) initiators are not 'terminating markup'
c) when two items of in-scope terminating markup have a common prefix, the parser must give precedence to the longest item.
d) when two items of in-scope terminating markup have exactly the same value, the parser must give precedence to the innermost ( most deeply nested ) item.
e) when the separator and terminator on a group have exactly the same value, the parser must give precedence to the separator.

If an initiated component can occur at the same point as an item of terminating markup, the initiator takes precedence.

regards,

Tim Kimber, Common Transformation Team,
Hursley, UK
Internet: kimbert@uk.ibm.com
Tel. 01962-816742
Internal tel. 246742

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