execute method

@override List execute(List results, Map<String, dynamic> passed)

The iterable, nested function that evaluates the entire FHIRPath expression one object at a time

Implementation

@override
List execute(List results, Map<String, dynamic> passed) {
  final executedBefore = before.execute(results.toList(), passed);
  if (executedBefore.length != 1) {
    throw FhirPathEvaluationException(
        'The "as" operation requires a left operand with 1 item, '
        'but was passed the following\n'
        'Operand 1: $before',
        operation: 'as',
        arguments: before,
        collection: results);
  } else if (after.length != 1 || after.first is! IdentifierParser) {
    throw FhirPathEvaluationException(
        'The "as" operation requires a right operand that '
        'has a single item that resolves to an identifier, but was passed:\n'
        'Operand 2: $after',
        operation: 'as',
        arguments: after,
        collection: results);
  }
  final identifierValue = (after.first as IdentifierParser).value;
  if (((passed.isVersion(FhirVersion.r4)
              ? r4.resourceTypeFromStringMap.keys.contains(identifierValue)
              : passed.isVersion(FhirVersion.r5)
                  ? r5.resourceTypeFromStringMap.keys
                      .contains(identifierValue)
                  : passed.isVersion(FhirVersion.dstu2)
                      ? dstu2.resourceTypeFromStringMap.keys
                          .contains(identifierValue)
                      : stu3.resourceTypeFromStringMap.keys
                          .contains(identifierValue)) &&
          executedBefore.first is Map &&
          executedBefore.first['resourceType'] == identifierValue) ||
      (identifierValue.toLowerCase() == 'string' &&
          (executedBefore.first is String)) ||
      (identifierValue.toLowerCase() == 'boolean' &&
          (executedBefore.first is bool ||
              executedBefore.first is FhirBoolean)) ||
      (identifierValue.toLowerCase() == 'integer' &&
          (executedBefore.first is int ||
              executedBefore.first is FhirInteger)) ||
      (identifierValue.toLowerCase() == 'decimal' &&
          (executedBefore.first is double ||
              executedBefore.first is FhirDecimal)) ||
      (identifierValue.toLowerCase() == 'date' &&
          executedBefore.first is FhirDate) ||
      (identifierValue.toLowerCase() == 'datetime' &&
          (executedBefore.first is DateTime ||
              executedBefore.first is FhirDateTime)) ||
      (identifierValue.toLowerCase() == 'time' &&
          executedBefore.first is FhirTime) ||
      (identifierValue == 'quantity' &&
          executedBefore.first is FhirPathQuantity)) {
    return executedBefore;
  }

  if (FhirDatatypes.contains(identifierValue)) {
    final polymorphicString = 'value$identifierValue';
    final polymorphicIdentifier = IdentifierParser(polymorphicString);
    final polymorphicParserList = ParserList([polymorphicIdentifier]);
    return polymorphicParserList.execute(results.toList(), passed);
  }
  return [];
}