Using the same value on either side of a binary operator is almost always a mistake. In the case of logical operators, it is either a copy/paste
error and therefore a bug, or it is simply wasted code, and should be simplified. In the case of arithmetic operators, having the same value on both
sides of an operator yields predictable results, and should be simplified.
Noncompliant code example
* always true
IF X = X
PERFORM SECTION1.
END-IF.
* always false
IF X <> X
PERFORM SECTION2.
END-IF.
* if the first one is true, the second one is too
IF X = Y AND X = Y
PERFORM SECTION3.
END-IF.
* if the first one is true, the second one is too
IF X = Y OR X = Y
PERFORM SECTION4.
END-IF.
* always 1
COMPUTE X = Y / Y.
* always 0
COMPUTE X = Y - Y.
Exceptions
This rule ignores * and +.
