EXPRESS 1.0b2 FTF Avatar
  1. OMG Issue

EXPRESS — Correct/explain the type model for InParameter

  • Key: EXPRESS-1
  • Legacy Issue Number: 13686
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    In Figure 26, InParameter inherits :formal-parameter-type (ParameterType) from Parameter. In Figure 27, InParameter inherits variable-type (VariableType) from NamedVariable. InParameter cannot have both.
    Proposed Resolution:
    Actually it can. The problem is that InParameter has two faces: the formal parameter has a ParameterType, but the corresponding internal Variable in each invocation has a VariableType - any GeneralizedType becomes the ActualType of the actual parameter. And VARParameter has the same behavior - the Parameter can have a GeneralizedType, but each instantiation refers to a "variable" that has an ActualType. Modify the text to explain this better.

  • Reported: EXPRESS 1.0b1 — Thu, 12 Mar 2009 04:00 GMT
  • Disposition: Resolved — EXPRESS 1.0b2
  • Disposition Summary:

    After some discussion of elaborating the model, the FTF concluded to adopt the proposed resolution and modify the text to explain the two relationships for InParameter.
    But VARVariables do not have variable-types; VARVariables only have referents. Also, ControlVariables are Variables (they can be passed to VAR Parameters, even though they cannot be assigned to). This all means that variable-type should be an attribute of Variable instead of NamedVariable. QueryVariables do have variable-types, and in order to simplify the model, they are to become a subclass of Variable, instead of NamedVariable, although it is syntactically impossible for a QueryVariable to be the referent of a VARCell.
    Finally, documents Parameter:variable, an association that no longer exists with the Beta-2 model of InParameter and VARParameter. This will also be corrected.

  • Updated: Fri, 6 Mar 2015 20:58 GMT