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Syntax Definition cneg 9829
 Description: Extend class notation to include unary minus. The symbol -u is not a class by itself but part of a compound class definition. We do this rather than making it a formal function since it is so commonly used. Note: We use different symbols for unary minus (-u) and subtraction cmin 9828 ( ) to prevent syntax ambiguity. For example, looking at the syntax definition co 6296, if we used the same symbol then "( A ) " could mean either " A " minus " ", or it could represent the (meaningless) operation of classes " " and " " connected with "operation" " ". On the other hand, " " is unambiguous.
Hypothesis
Ref Expression
cA
Assertion
Ref Expression
cneg