simpleLiteral
A restricted literal used in simple path indexer positions. Accepts only string literals and number literals, excluding the richer set of values available in the full literal rule.
Examples
String literal in an indexed path
[Condition: coding['code'] in "Diabetes"]
Number literal in an indexed path
[Condition: coding[0] in "Diabetes Codes"]
EBNF
simpleLiteral : STRING | NUMBER ;