IBM SC34-5764-01 - Manual (Page 88)

In the two preceding examples, notice the positional relationships between long and length, and wide and
width
. Also notice how information is received from variable perim. Both programs include perim on a
RETURN instruction. For the program with a subroutine, the language processor assigns the value in
perim
to the special variable RESULT. For the program using a function, the language processor replaces
the function call perimeter(long,wide) with the value in perim.
Using the ARG Built-in Function: Another way for a subroutine or function to receive arguments is with
the ARG built-in function. This function returns the value of a particular argument. A number represents the
argument position.
For instance, in the previous example, instead of the ARG instruction:
ARG length, width
you can use the ARG function as follows:
length = ARG(1) /* puts the first argument into length */
width = ARG(2) /* puts the second argument into width */
For more information about the ARG function see section “ARG” on page 134.
Receiving Information from a Subroutine or Function
Although a subroutine or function can receive up to 20 arguments, it can specify only one expression on
the RETURN instruction. That expression can be:
v A number
RETURN 55
v One or more variables whose values are substituted (or their names if no values have been assigned).
RETURN value1 value2 value3
v A literal string
RETURN 'Work complete.'
v An arithmetic, comparison, or logical expression whose value is substituted.
RETURN 5 * number
This program receives as arguments the length and width of a
rectangle and passes that information to an internal function,
named perimeter. The function then calculates the perimeter of
the rectangle.
/***********************************REXX***********************************/
/* */
/* */
/* */
/* */
/*****************************************************************************/
PARSE ARG long wide
SAY ‘The perimeter is’ perimeter (long,wide) ‘inches.’
EXIT
perimeter:
ARG length, width
perim = 2 * length + 2 * width
RETURN perim
Figure 40. Example of Passing Arguments on the Call to an Internal Routine
Writing Subroutines and Functions
66 CICS TS for VSE/ESA: REXX Guide