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A MethodSignature defines the parameters and return values for a method. The MethodSignature improves traceability while enhancing the ability for automation engines to execute a MethodDef's FormalExpression. A MethodSignature is an optional a required element of every MethodDef. MethodSignature Parameters and ReturnValues are optional. An empty MethodSignature may be used to explicitly indicate that the method does not take any input parameters or return any values. Most Methods use one or more input parameters and return one or more values. MethodDefs associated with ItemRefs may only return a single value. MethodDefs associated with ItemGroupDefs must return one value per ItemRef.
One MethodSignature element is optional required for the MethodDef and ConditionDef elements, and in the RangeCheck element when a FormalExpression is used. In cases where a MethodSignature element exists without an associated FormalExpression, the MethodSignature supports improved traceability. It also serves the case where one role defines the MethodDef or ConditionDef, but another role provides the executable FormalExpression.
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