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Re^4: A "but" operator.by Plankton (Priest) 
on Sep 27, 2004 at 20:30 UTC ( #394340=note: print w/ replies, xml )  Need Help?? 
I think you are trying to say a "but" operator is equivalent "not and" operator and that !(A>B) is equivalent to "but". I am assuming that "!" symbolizes the negation operator and ">" symbolized the ifthen ( or implies ) operator. Yet ...
As far a what a but operator is I would say it should be equivalent to the "Boolean And" operator. And is not needed in a programming language. The word "but" is used in commonly to emphasis that an assumption is false. Example ... If a student where to errorously assume that multiplaction is the same as addition the student might state ... 1 + 1 = 2 and 2 + 2 = 4 and 2 * 2 = 4 and 1 * 1 = 2 ... which we know to be false. The student's teacher would say ... 1 + 1 = 2 and 2 + 2 = 4 and 2 * 2 = 4 but 1 * 1 != 2 ... to correct the student. This is the same as 1 + 1 = 2 and 2 + 2 = 4 and 2 * 2 = 4 and 1 * 1 != 2 T and T and T and T is TRUE It is not equal to 1 + 1 = 2 and 2 + 2 = 4 and 2 * 2 = 4 and not (1 * 1 != 2) T and T and T and F is FALSE But merely gives emphasis to the fact that the student's assumption is false. Janitored by davido: removed excess spaces within pre tags that caused horizontal scrolling.
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