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1 ;; Some conditions we might want to be able to signal
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2
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3 (define-condition undefined-action (condition)
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4 ;; This condition would apply to an attempt to perform a meaningless
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5 ;; operation on an object. This may, initially, include things that
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6 ;; are a pain to implement but should really be used when it's
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7 ;; genuinely unclear what an operation means in the given
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8 ;; context. In such cases, a condition handler might be the best
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9 ;; approach anyway.
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10 ((operation :initarg :operation
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11 :reader undefined-action-operation)
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12 (datatype :initarg :datatype
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13 :reader undefined-action-datatype))
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14 (:report (lambda (condition stream)
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15 (format stream "The consequence of performing ~A on and object of type ~A is undefined"
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16 (undefined-action-operation condition)
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17 (undefined-action-datatype condition)))
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18
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19 (define-condition insufficient-information (condition)
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20 ;; It should be possible to construct genuinely minimal musical
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21 ;; structures. When the information in these is insufficient to
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22 ;; answer a query, this condition should be raised.
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23 ((operation :initarg :operation
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24 :reader insufficient-information-operation)
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25 (datatype :initarg :datatype
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26 :reader insufficient-information-datatype))
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27 (:report (lambda (condition stream)
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28 (format stream "The ~A object does not contain enough information to perform ~A"
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29 (insufficient-information-datatype condition)
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30 (insufficient-information-operation condition)))
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31
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32
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