public Collection<? extends AttributeValue> getFlattenedValues() {
            if (flattened == null) {
                List<AttributeValue> result = new ArrayList<>(values.size());
                for (AttributeValue value : values) {
                    // Projections need to be flattened!
                    if (value instanceof Projection) {
                        result.addAll(((Projection) value).getFlattenedValues());
                    } else {
                        result.add(value);
                    }
                }
                flattened = result;
            }

            return flattened;
        }
Computes the flattened values of the projection.

@return Returns the flattened values of the projection.
smithy-model/src/main/java/software/amazon/smithy/model/selector/AttributeValueImpl.java