Functions

PRX ships with an extensive library of predefined functions, offering a wide array of functionality for various tasks. Each function within PRX is designed to accept zero or more parameters, each parameter being of a specific type. These functions also support overloading, enabling them to handle different parameter combinations and return values of specific types. A function can either be used in place of values that correspond to their return value type or directly within rules.

Usage

In-Place

Functions can be utilized as substitutes for values that yield identical return types.

/* create new variable */
SET &TEST_VAR = "Hello World";

/* get length + 5 */
SET &TEST_LEN = 5 + LENGTH(&TEST_VAR);    /* <-- equals 16 */

In the preceding example, we've created a variable TEST_VAR and used the LENGTH-function to store its length (+5) into another variable TEST_LEN.

Function Call

Another way of using them is by calling them directly.

/* make a function call */
CALL SAY("Hello World");

In this example, we've used the SAY-function to print text to the SYSPRINT log file. When we call a function using the CALL-statement, we effectively create a new rule. More information on rules will be provided in the next chapter.