This use case is valuable when using expressions in a MongoDB Query (that start with $) on fields when the field is stored in a constant field.

Note: as part of this ticket, let's create additional tickets, e.g. supporting string builders. We don't need to prioritize for public preview but we should keep track of the edge cases.

private final String FIELD = "field";
"$" + FIELD; // does not work

"$" + "field"; // does not work either