List of values

Not all parameters can accept a list of values. A list parameter can be defined to accept a specific set of multiple values that can be of one or more types. Values in the list must be separated by one or more blanks. Each list of values is enclosed by parentheses, indicating that the list is treated as a single parameter. Parentheses are used even when a parameter is specified in positional form. To determine whether a list can be specified for a parameter, and what kind of list it can be, refer to the parameter description under the appropriate command description.

A list parameter can be defined to accept a list of multiple like values (a simple list) or a list of multiple unlike values (a mixed list). Each value in either kind of list is called a list element. List elements can be constants, variables, or other lists; expressions are not allowed.

• A simple list parameter accepts one or more values of the type allowed by a parameter. For example, (RSMITH BJONES TBROWN) is a simple list of three user names.
• A mixed list parameter accepts a fixed set of separately defined values that are in a specific order. Each value can be defined with specific characteristics such as type and range. For example, LEN(5 2) is a mixed list in which the first element (5) gives the length of a field and the second element (2) gives the number of decimal positions in that field.
• For many parameters defined to accept lists, predefined single values can be specified in place of a list of values. One of these single values can be the default value, which can be either specified or assumed if no list is specified for a simple or mixed list. To determine what defaults are accepted for a given list parameter, refer to the description of the parameter in the description of the command for which the parameter is defined and used.

  Note: *N cannot be specified in a simple list, but it can be specified in a mixed list. Also, individual parameters passed on the CALL and CALLPRC commands cannot be lists.

• The maximum level of nesting of lists inside lists is three, including the first. These are indicated by three nested levels of parentheses.

Here are examples of lists.

The last two examples contain two lists nested inside a list: the first list contains values of A and B, and the second list contains values of 1 and 2. The space between the two nested lists is not required. Blanks are the separators between the values inside each nested list, and the sets of parentheses group the nested values into larger lists.