Method unparse

core/src/main/java/org/apache/calcite/sql/SqlSyntax.java:33–40

(
        SqlWriter writer,
        SqlOperator operator,
        SqlCall call,
        int leftPrec,
        int rightPrec)

   */
  FUNCTION {
    @Override public void unparse(
        SqlWriter writer,
        SqlOperator operator,
        SqlCall call,
        int leftPrec,
        int rightPrec) {
      SqlUtil.unparseFunctionSyntax(operator, writer, call, false);
    }
  },

  /**