/* REXX */

/* Arrays are built by appending a period and an index to a variable name */
/* Typically the size of the array is stored in index 0                   */

/* Build a list of 50 prime numbers */

list.0= 0
z= 3

DO WHILE list.0<50 
    IF \ HAS_DIVIDERS(z) THEN DO  /* IF NOT ... THEN */
        list.0= list.0+1
        ind= list.0
        list.ind= z
    END

    z= z+2
END

DO i=1 TO list.0
    SAY list.i
END

EXIT


/* Below is a function.  The word PROCEDURE was added, to give it a     */
/* local variable pool.  Exchange of data with the calling program is   */
/* done through argument passing and result return mechanism.           */
HAS_DIVIDERS: PROCEDURE 
    /* Pick up first (and only) argument */
    z= ARG(1)
    result= 0

    DO i=2 TO z-1
        IF (z//i)=0 THEN DO
            /* leave loop if i is a divider of z */
            result= 1
            LEAVE i
        END 
    END

    RETURN result