Code Examples

Reference modification is akin to substringing in other programming languages. Reference modification is very useful for referencing a component part of a composite string. For example, it might be used to reference the area code digits of a 10-character string containing a phone number (area code + seven digits):

01  PHONE-NUMBER  PIC 9(10) VALUE 3017728134.
{ . . . }
PHONE-NUMBER (1:3).
*The reference modification begins at position 1
*of string PHONE-NUMBER and has a length of 3.
*The reference modification value = "301"

For the following code examples, assume these data items:

01 ACCOUNT-CODE PIC X(20) VALUE "AB700648xSMITHxxCLA1".
01 ACCOUNT-NAME PIC X(6)  VALUE ALL SPACES.
01 ACCT-CLASS-1 PIC X(4)  VALUE "CLA1".

Code example 1:

MOVE ACCOUNT-CODE (10:6) TO ACCOUNT-NAME.
*This reference modification selects the
*characters that form the name portion of
*ACCOUNT-CODE.  The reference starts at position
*10 and has a length of 6 characters.
*The ACCOUNT-CODE substring = "SMITHx"

Code example 2:

IF ACCOUNT-CODE (17:) = ACCT-CLASS-1 THEN
*When the reference modification does not
*include a length, the reference begins at the
*value specified and extends to the end of the
*data item.
*The ACCOUNT-CODE substring = "CLA1"