HP 3000 Manuals

HP Transact Reference Manual

Data Item Names 

The first character of a data item name must be alphanumeric.  Subsequent
characters can be either alphabetic (A through Z), numeric (0 through 9),
or any ASCII character other than the following characters:  , ; :  = < >
( ) " or blank.  The name can be from 1 to 16 characters long.  For
example, data items in Figure 2-1 include CUST-NAME, ORDER-DATE,
ORDER-NUMBER, and AMOUNT-DUE.

When you are referring to the specific value of a data item that is in
the data register, you must enclose the name in parentheses.  (Registers
are discussed in detail in Chapter 4.)  When you are referring to the
name of the data item--its location in the list register--do not enclose
the name in parentheses.  Notice the difference between

     LIST CUST-NO;

which reserves space for CUST-NO in the list register, and

     LET (CUST-NO)= 123;

which manipulates the value of CUST-NO.

MPE/iX 5.0 Documentation