Introduction › Reading Syntax Diagrams › Punctuation Marks or Arithmetic Symbols

Punctuation Marks or Arithmetic Symbols

If punctuation marks or arithmetic symbols are shown with a keyword or variable, they must be entered as part of the statement or command. Punctuation marks and arithmetic symbols can include:

The following is an example of a statement without parameters.

►►─ COMMAND ──────────────────────────────────────────────────────────────────►◄

You must write:

COMMAND

Required parameters appear on the same horizontal line (the main path of the diagram) as the command or statement. The parameters must be separated by one or more blanks.

►►─ COMMAND ─ PARM1 ─ PARM2 ──────────────────────────────────────────────────►◄

You must write:

COMMAND PARM1 PARM2

Delimiters such as parentheses around parameters or clauses must be included.

►►─ COMMAND ─ (PARM1.) ─ PARM2='variable' ────────────────────────────────────►◄

If the word "variable" is a valid entry, you must write:

COMMAND (PARM1) PARM2='variable'

Where you see a vertical list of parameters as shown in the following example, you must choose one of the parameters. This indicates that one entry is required and only one of the displayed parameters is allowed in the statement.

►►─ COMMAND ─┬─ PARM1 ─┬──────────────────────────────────────────────────────►◄
             ├─ PARM2 ─┤
             └─ PARM3 ─┘

You can choose one of the parameters from the vertical list, such as in the following examples:

COMMAND PARM1
	COMMAND PARM2
     	COMMAND PARM3

A single optional parameter appears below the horizontal line that marks the main path. When a required parameter in a syntax diagram has a default value, it indicates the value for the parameter if the command is not specified. If you specify the command, you must code the parameter and specify one of the displayed values.

►►─ COMMAND ─ PARM1= ─┬─ YES ◄ ─┬─ PARM2 ─────────────────────────────────────►◄
                      └─ NO ────┘

If you specify the command, you must write one of the following:

COMMAND PARM1=NO PARM2
COMMAND PARM1=YES PARM2

►►─ COMMAND ─┬─────────────┬──────────────────────────────────────────────────►◄
             └─ PARAMETER ─┘

You can choose (or not) to use the optional parameter, as shown in the following examples:

COMMAND
COMMAND PARAMETER

If you have a choice of more than one optional parameter, the parameters appear in a vertical list below the main path.

►►─ COMMAND ─┬─────────┬──────────────────────────────────────────────────────►◄
             ├─ PARM1 ─┤
             └─ PARM2 ─┘

You can choose any of the parameters from the vertical list, or you can write the statement without an optional parameter, such as in the following examples:

COMMAND
	COMMAND PARM1
     	COMMAND PARM2

For some statements, you can specify a single parameter more than once. A repeat symbol (a backward-pointing arrow above the main horizontal line) indicates that you can specify multiple parameters. The following examples include the repeat symbol.

             ┌────────────┐
►►─ COMMAND ─▼─ variable ─┴───────────────────────────────────────────────────►◄

In the above example, the word "variable" is in lowercase italics, indicating that it is a value you supply, but it is also on the main path, which means that you are required to specify at least one entry. The repeat symbol indicates that you can specify a parameter more than once. Assume that you have three values named VALUEX, VALUEY, and VALUEZ for the variable. Some of your choices are:

COMMAND VALUEX
     COMMAND VALUEX VALUEY
     COMMAND VALUEX VALUEX VALUEZ

If the repeat symbol contains punctuation such as a comma, you must separate multiple parameters with the punctuation. The following example includes the repeat symbol, a comma, and parentheses.

                 ┌─ , ────────┐
►►─ COMMAND ─ ( ─▼─ variable ─┴─ .) ──────────────────────────────────────────►◄

In the above example, the word "variable" is in lowercase italics, indicating that it is a value you supply. It is also on the main path, which means that you must specify at least one entry. The repeat symbol indicates that you can specify more than one variable and that you must separate the entries with commas. The parentheses indicate that the group of entries must be enclosed within parentheses. Assume that you have three values named VALUEA, VALUEB, and VALUEC for the variable. Some of your choices are:

COMMAND (VALUEC)
     COMMAND (VALUEB,VALUEC)
     COMMAND (VALUEB,VALUEA)
     COMMAND (VALUEA,VALUEB,VALUEC)

The following example shows a list of parameters with the repeat symbol.

             ┌─────────────┐ ┌─────────────┐ ┌─────────────┐
►►─ COMMAND ─▼─┬─────────┬─┴─▼─┬─────────┬─┴─▼─┬─────────┬─┴──────────────────►◄
               └─ PARM1 ─┘     └─ PARM2 ─┘     └─ PARM3 ─┘

Some choices you can make include:

COMMAND PARM1
     COMMAND PARM1 PARM2 PARM3
     COMMAND PARM1 PARM1 PARM3

When a parameter in a syntax diagram is above the line, for example, YES in the following diagram, its special treatment indicates it is the default value for the parameter. If you do not include the parameter when you write the statement, the result is the same as if you had actually specified the parameter with the default value.

►►─ COMMAND ─┬──────────────────────┬─ PARM2 ─────────────────────────────────►◄
             └─ PARM1= ─┬─ YES ◄ ─┬─┘
                        └─ NO ────┘

Because YES is the default in the example above, if you write:

COMMAND PARM2

you have written the equivalent of:

COMMAND PARM1=YES PARM2

In some syntax diagrams, a set of several parameters is represented by a single reference, as in this example:

►►─ COMMAND ─┬─────────────────────┬──────────────────────────────────────────►◄
             ├─ PARM1 ─────────────┤
             └─┤ parameter-block ├─┘

Expansion of parameter-block

├──┬─────────────────────┬─────────────────────────────────────────────────────┤
   ├─ PARM2 ─────────────┤
   └─ PARM3 ─┬─────────┬─┘
             ├─ PARM4 ─┤
             └─ PARM5 ─┘

The "parameter-block" can be displayed in a separate syntax diagram.

Choices you can make from this syntax diagram therefore include (but are not limited to) the following:

COMMAND PARM1
     COMMAND PARM3
     COMMAND PARM3 PARM4

Note: Before you can specify PARM4 or PARM5 in this command, you must specify PARM3.