Side Effect Functions

If, in

    rezzy = funky1(a,b,c) + funky2(a,b,c)

funky1 and funky2 modify the value of, a then the order of execution could be important. Consider:

    INTEGER FUNCTION funky1(a,b,c)
     ...
    a = a*a
    funky1 = a/b

and

    INTEGER FUNCTION funky2(a,b,c)
     ...
    a = a*2
    funky2 = a/c

With a=4, b=2 and c=4 the following happens:

• if funky1 executed first then rezzy=8+8=16
• if funky2 executed first then rezzy=2+32=34

A properly constructed function should not change its arguments or any global entities.

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