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A FormalExpression used within a ConditionDef or a RangeCheck must evaluate to True or False. A FormalExpression referenced within a MethodDef having Type Imputation, Computation, or Transpose must evaluate to the correct DataType for an Item that may be imputed or computed using the Method. A FormalExpression gets parameter and return value definitions from the MethodSignature element. The data types in the MethodSignature parameters and return values must match the corresponding data types in the FormalExpression.
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