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  1. OMG Issue

SYSML11 — 10 Constraint Blocks, 10.3.2.1 ConstraintBlock

  • Key: SYSML11-87
  • Legacy Issue Number: 12132
  • Status: closed  
  • Source: No Magic, Inc. ( Darren Kelly)
  • Summary:

    10 Constraint Blocks and 10.3.2.1 ConstraintBlock: parameters never clearly defined SysML1.0, 10 Constraint Blocks: 'A constraint block is defined by a keyword of «constraint» applied to a block definition. The properties of this block define the parameters of the constraint.' The above does not make clear that parameters are properties that can be typed by a ValueType (yet are not value properties), and it does not exclude nested contraints, which are properties typed by a <<ConstraintBlock>> (although other sentences elsewhere in the specification do make that clearer). Also, it is not clear whether a constraint parameter can be typed by a block (although there are no examples of such in the figures). Rewrite to specify what constraint parameters are: 'A constraint block is defined by a keyword of «constraint» applied to a block definition. The properties of this block typed by a ValueType, Unit, or DataType define the parameters of the constraint.' SysML1.0, 10.3.2.1 ConstraintBlock: '.. A constraint block typically defines one or more constraint parameters, which are bound to properties of other blocks in a surrounding context where the constraint is used.' Rewrite to explain what constraint parameters are: '.. A constraint block typically defines one or more constraint parameters, which are bound to properties of other blocks in a surrounding context where the constraint is used. Constraint parameters are properties of a Constraint Block that are typed by either a ValueType, a Unit, or a DataType.' (NB: the resolutions suggested here depends on the unit, value, dimension metamodel being changed to admit the application of Unit as a type.) This matter could be greatly simplified by including a ConstraintParameter stereotype as a point of documentation and specification

  • Reported: SysML 1.0 — Wed, 2 Jan 2008 05:00 GMT
  • Disposition: Resolved — SysML 1.1
  • Disposition Summary:

    SysML does not restrict the type of parameters to which constraint blocks may be
    applied. Even though the typical examples apply parametric constraints to value
    parameters, such as mathematical expressions that constrain numeric property
    values, constraint blocks may also be applied to structural properties such as parts or
    reference properties.
    Reword the explanatory sentence referenced by the issue from the final introduction
    paragraph to avoid suggesting that constraint parameters are the only kind of
    property a constraint block may contain. Also, avoid language that excludes recursive
    definition of constraint blocks, in which a nested constraint property references the
    same constraint block being defined.

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