How to put literal numbers into a query dynamically?

[fansek]

In my project, I generate a group by clause of a query dynamically from a specified field list.
In PostgreSQL, it is possible to refer to an output column in a group by clause by its ordinal number, such as in the following example:

select t.c, count(*)
from t
group by 1

Currently, I am using slonik's raw tag to place a literal number into a query based on which fields need to be put into a group by clause, such as in the following snippet:

const indices = projection
  .flatMap((spec, index) => (spec.aggregated ? [] : [index + 1]))
  .map((index) => raw(String(index)));
const optionalGroupByClause = indices.length === 0
  ? sql.fragment``
  : sql.fragment`group by ${sql.join(indices, sql.fragment`, `)}`;

Is it possible to do it without the use of raw tag?
I thought, that literalValue may help, but it accepts only strings. Is there a reason not to allow other primitive values to be used with that function? Thank you.