( )
 Function or grouping indicator                  (Special)
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 Description

     Parentheses (()) in expressions group certain operations for readability
     or to force a particular evaluation order.  Parentheses also identify a
     function call.

     When specifying the grouping operator, the item that falls within the
     parentheses must be a valid expression.  Subexpressions may be further
     grouped.

     For function calls, a valid function name must precede the left
     parenthesis, and the function arguments, if any, must be contained
     within the parentheses.

 Examples

     .  This example changes the default order of expression
        evaluation:

        ? 5 * (10 + 6) / 2         // Result: 40

     .  The next example shows a function call:

        x := SQRT(100)