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by tsm 4787 days ago 

    (1+ 'A)
1 comments
ohyes 4787 days ago
Symbol A is not of type number.

(1+ a)

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gsg 4787 days ago
A++ is a grade, not a number. Clearly what you need is #S(grade :letter A :decorations (+ +) :rapidly-escalating-pedantry t) or some other meaningful representation.
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