code: function buildInitStatement(metadata, exportNames, initExpr) {
    return t.expressionStatement(
      exportNames.reduce(
        (acc, exportName) =>
          template.expression`EXPORTS.NAME = VALUE`({
            EXPORTS: metadata.exportName,
            NAME: exportName,
            VALUE: acc,
          }),
        initExpr,
      ),
    );
  }
docs: Given a set of export names, create a set of nested assignments to
  initialize them all to a given expression.