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reservedWord

The subset of CQL keywords that may not appear as identifiers in ambiguous contexts. Reserved words include core operators, literals, and structural keywords. Non-reserved keywords (keywordIdentifiers) may be used as names.

Examples

Reserved word as operator — cannot be used as identifier

-- 'and', 'or', 'not', 'null', 'true', 'false' are reserved
"Has Diabetes" and "Has Hypertension"

Reserved word 'from' in a query

from [Condition] C where C.clinicalStatus ~ "Active"

Attempting to use a reserved word as name requires quoting

-- Must use backtick or double-quote to use reserved words as identifiers
define `true`: 42

Railroad Diagram

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EBNF

reservedWord
  : 'aggregate' | 'all' | 'and' | 'as' | 'after' | 'before' | 'between'
  | 'case' | 'cast' | 'Code' | 'collapse' | 'Concept' | 'convert' | 'day'
  | 'days' | 'difference' | 'distinct' | 'duration' | 'during' | 'else'
  | 'exists' | 'expand' | 'false' | 'flatten' | 'from' | 'if' | 'in'
  | 'included in' | 'is' | 'hour' | 'hours' | 'Interval' | 'let' | 'List'
  | 'maximum' | 'millisecond' | 'milliseconds' | 'minimum' | 'minute'
  | 'minutes' | 'month' | 'months' | 'not' | 'null' | 'occurs' | 'of'
  | 'on or' | 'or' | 'or on' | 'per' | 'point' | 'properly' | 'return'
  | 'same' | 'second' | 'seconds' | 'singleton' | 'sort' | 'such that'
  | 'then' | 'to' | 'true' | 'Tuple' | 'week' | 'weeks' | 'when' | 'with'
  | 'within' | 'without' | 'year' | 'years'
  ;