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| Description: Extend class notation to include the value of an operation F (such as +) for two arguments A and B. Note that the syntax is simply three class symbols in a row surrounded by parentheses. Since operation values are the only possible class expressions consisting of three class expressions in a row surrounded by parentheses, the syntax is unambiguous. (For an example of how syntax could become ambiguous if we are not careful, see the comment in cneg 5273.) |
| Ref | Expression |
|---|---|
| cA | class A |
| cB | class B |
| cF | class F |
| Ref | Expression |
|---|---|
| co | class (AFB) |
| Colors of variables: wff set class |