2024-03 - SysML v2 Pilot Implementation

This is an incremental update to the 2024-02 release. It corresponds to Eclipse plugin version 0.40.0.

New Features

None.

Backward Incompatibilities

None.

Issue Resolutions

None.

Jupyter

Bug fixes.

Visualization (PlantUML)

Bug fixes.

Technical Updates

1. Metamodel operations. The implementation of all OCL operations from the metamodel specifications has been moved from in-line method code in metamodel Impl classes into separate delegate classes, using the Eclipse "invocation delegate" mechanism.
   [PR #554] [PR #555]

2. Maven build. The Maven build was updated to resolve a problem introduced by a newly released version of a plugin used by the tycho-build extension.
   [PR #550 ]

Bug Fixes

1. Standard library element rendering (PlantUML). Corrects the rendering of standard library elements in compartments when SHOWLIB and SHOWINHERITED styles are not used.
   [PR #548]
2. Bindings with standard library metadata (Jupyter). Fixes a bug introduced in the 2024-02 release that caused bindings of enumeration features of metadata usages of metadata definitions from library models to spuriously cause warnings in the Jupyter environment (but not in Eclipse).
   [PR #551]
3. Resolution of results, subjects and objectives. Fixes a bug that caused the incorrect resolution of names of result parameters, subject parameters and objectives that were physically inserted into the abstract syntax tree after parsing.
   [PR #552]
4. Implicit subsetting of occurrenceUsages. Fixes the implementation of the implicit subsetting of occurrenceUsages that are suboccurrences.
   [PR #553]
5. %viz command (PlantUML, Jupyter). Fixes a bug caused by the changes in PR #552 in which the %viz command in the Jupyter environment would sometimes throw a ConcurrentModificationException.
   [PR #557]

2024-02 - SysML v2 Pilot Implementation

This is an incremental update to the 2024-01 release. It corresponds to Eclipse plugin version 0.39.0.

New Features

KerML

1. Comment locale. In the KerML abstract syntax, a Comment may have a locale specified, which includes "identification of the language of the body text and, optionally, the region and/or encoding", using the international standard notation. The textual notation has now been updated to allow the locale to be specified for a comment.

   locale"en_US" /* This is US English comment text. */

   [PR #540]

2. Keywords on metadata. User-defined keywords are now allowed on metadata features. (Keywords were already allowed on metaclasses.)

   #keyword metadataM;

   [PR #540]

SysML

3. Comment locale. The SysML textual notation has been updated to allow the locale for a comment to be specified, using the same syntax as given for KerML above.
   [PR #542]

4. Perform action effective names. Previously, the effective name of a perform action usage was given solely by the name of its performed action (and similarly for exhibit state usages and include use case usages). If the perform action usage did not specify a performed action, and had no declared name, then it also had no effective name. This has now been changed so that a perform action usage without a performed action acts like a regular usage, so that, if it has a redefinition, that determines its effective name.

   abstract part def P {
       abstract perform action A;
    }
    abstract part def P1 :> P {
        abstract perform action redefines A; // Effective name is "A".
    }
    part def P2 :> P {
        perform B redefines A; // Effective name is "B".
    }
   

   [PR #542]

5. Keywords on metadata and enumerations. User-defined keywords are now allowed on metadata definitions, metadata usages, enumeration definitions and enumerated values within enumeration definitions (keywords were already allowed on enumeration usages other than enumerated values).

   #keyword metadata defM;
#keyword metadataM;
#keyword1 enum defE {
    #keyword2 enume;
}

   [PR #542]

Backward Incompatibilities

1. Exponentiation. Previously the exponentiation operators (** and ^) where left-associative, similarly to the additive and multiplicative operators. That is, an expression such as 2 ^ 3 ^ 4 was parsed as (2 ^3) ^ 4. This has been changed so that the exponentiation operators are right-associative, which is the normal expectation for exponentiation. So, 2 ^ 3 ^ 4 now parses as 2 ^ (3 ^ 4).
   [PR #540]

Issue Resolutions

KerML

1. KerML Metamodel. The KerML abstract and concrete syntax have been updated consistent with the resolutions to the following KerML FTF issues. Other than as listed above, these changes will not affect user models.

   • KERML-22 Name all associations in the KerML abstract syntax
   • KERML-82 checkConnectorTypeFeaturing is not correct
   • KERML-98 Comment Locale not in textual notation
   • KERML-165 Exponentiation should be right-associative
   • KERML-307 User-defined keywords are not allowed on metadata features

   [PR #540]

2. KerML Model Libraries. Various models in the Kernel Model Libraries have been updated consistent with the resolutions to the following KerML FTF issues. In addition, the .meta.json and .project.json files in the model library directories have been updated to reflect the new normative KerML URI https://www.omg.org/spec/KerML/240201 and the versions have been updated to 1.0.0-beta2.

   • KERML-45 LinkObject is irreflexive
   • KERML-46 Intersection missing for some multiple specializations
   • KERML-120 FlowTransferBefore needs end feature declarations

   [PR #541]

SysML

3. SysML Metamodel. The SysML abstract and concrete syntax has been updated consistent with the resolutions to the following SysML v2 FTF issues.

   • SYSML2-85 Effective name is not correct for a redefined perform action usage
   • SYSML2-553 checkRequirementUsageObjectiveRedefinition is incorrect
   • SYSML2-631 User-defined keywords are not allowed on metadata
   • SYSML2-637 User-defined keywords are not allowed on enumeration definitions [see note]
   • SYSML2-643 Comment locale not in textual notation
   • SYSML2-783 Parsing KerML Feature elements from SysML textual notation

   [PR #542]

4. SysML Model Libraries. Various models in the Systems and Domain Model Libraries have been updated consistent with the resolutions to the following SysML v2 FTF issues. In addition, the .meta.json and .project.json files in the model library directories have been updated to reflect the new normative SysML URI https://www.omg.org/spec/SysML/240201 and the versions have been updated to 2.0.0-beta2. KerML library projects are now required to be version 1.0.0-beta2.

   • SYSML2-158 Example FrontAxle definition
   • SYSML2-634 VerificationCase::subVerificationCases is typed incorrectly

   [PR #543]

Jupyter

None.

Visualization (PlantUML)

1. Connection ends in compartments. The text for connection ends shown in compartments has been improved to be less cluttered, showing the just names of the referenced features.
   [PR #537]

Technical Updates

1. Metamodel files. The metamodel files listed below have been updated. The metamodel URIs have been updated with the new date stamp used for the Beta 2 submission to OMG:
   https://www.omg.org/spec/KerML/20240201
https://www.omg.org/spec/SysML/20240201

   org.omg.sysml/model

   • SysML.uml
   • SysML_only.uml
   • KerML_only.uml
   • SysML_xmi.uml
   • SysML_only_xmi.uml
   • KerML_only_xmi.uml
   • SysML.ecore
   • kerml.ecore

   [PR #534]

2. Schema files. The following JSON schema files have been updated for the new URIs.

   org.omg.sysml/json-schema

   • KerML.json
   • SysML.json

   [PR #534]

Bug Fixes

1. Inherited reference rendering. Corrected references to graphical renderings of inherited elements in the SHOWINHERITED style.
   [PR #538]
2. Lifeclass implicit specializations. Corrected the required implied specialization by a LifeClass of its containing individualDefinition.
   [PR #546]
3. direction property serialization. Fixed the missing serialization to XMI of the direction property of parameters owned via ParameterMembership.
   [PR #547]
4. elementId property serialization. Fixed the missing serialization to XMI of the elementId property of standard LibraryPackages.
   [PR #549]

2024-01 - SysML v2 Pilot Implementation

This is an incremental update to the 2023-11 release. It corresponds to Eclipse plugin version 0.38.0.

New Features

KerML

1. Feature values on connectors. The KerML textual notation now supports declaring feature values on connectors that either have no declared ends or ends declared within their body.

   abstract connectorc1;
   abstract connectorc2 = c1; // Previously did not parse.
connectorc3 = c1 { // Previously did not parse.
   end::> a;
   end::> b;
}

   [PR #528]

2. Model-level evaluable functions. Two additional model-level evaluable functions have been implemented.

   • Range construction operator '..'. An expression of the form e1...e2, in which e1 and e2 evaluate to integers, results in an ordered sequence of a range of sequential integers from the value of e1 to the value of e2, inclusive. For example, 1..3 evaluates to the sequence (1, 2, 3). If the value of e1 is greater than the value of e2, then the result is the empty sequence.
   • SequenceFunctions::excludes function. This function tests whether a value is excluded from a sequence. For example, excludes(1..3, 2) is false, while excludes(1..3, 0) is true. It is the inverse of the includes function, which was already implemented.

   [PR #526]

SysML

3. Keywords on control nodes. In the SysML textual notation, user-defined keywords are now allowed on control nodes (i.e., merge, decision, join and fork nodes).

   #keyword forkfork1;

   [PR #531]

Backward Incompatibilities

1. Type conjugation. The KerML textual notation no longer allows multiple conjugation parts on a type declaration (which was invalid anyway).
   [PR #528]

Issue Resolutions

KerML

1. KerML Metamodel. The KerML abstract and concrete syntax have been updated consistent with the resolutions to the following KerML FTF issues. Other than as listed above, these changes will not affect user models.

   • KERML-7 isDirection, definition, semantics
   • KERML-21 Add property for Annotations owned by an AnnotatingElement
   • KERML-24 Connector declaration does not allow a feature value
   • KERML-61 PrimaryExpressionMember production should generate a ParameterMembership
   • KERML-75 Specify default direction for the ownedParameterMember of a ParameterMembership
   • KERML-90 The MetadataFeature::metaclass multiplicity is too restrictive
   • KERML-109 Textual Syntax allows multiple ConjugationParts on a Type
   • KERML-154 Directed features inherited from a conjugated type not handled properly
   • KERML-155 Expression::result has an incorrect subsetting
   • KERML-194 validateRedefinitionDirectionConformance does not account for conjugation
   • KERML-199 validateMultiplicityRangeBoundResultTypes constraint is too strong
   • KERML-204 Behavior portions must be classified by the same behavior they are portions of
   • KERML-232 Additional problems with deriveFeatureType
   • KERML-248 Error in Expression modelLevelEvaluable operation OCL

   [PR #528]

2. KerML Model Libraries. Various models in the Kernel Model Libraries have been updated consistent with the resolutions to the following KerML FTF issues.

   • KERML-25 Reflective KerML abstract syntax model has inconsistencies
   • KERML-44 Spatial links can be occurrences
   • KERML-49 Some readonly features are intended to have changing values
   • KERML-158 InsideOf association end feature redefines cross feature
   • KERML-231 LinkObject disjointness is redundant

   [PR #529]

SysML

3. SysML Metamodel. The SysML abstract and concrete syntax has been updated consistent with the resolutions to the following SysML v2 FTF issues. Other than as listed above, these changes will not affect user models.

   • SYSML2-430 Subsetting of subjectParameter properties is wrong
   • SYSML2-499 Assignments parsed without a target will fail validateAssignmentActionUsageArguments
   • SYSML2-616 User-defined keywords are not allowed on control nodes

   [PR #531]

4. SysML Model Libraries. Various models in the Systems and Domain Model Libraries have been updated consistent with the resolutions to the following SysML v2 FTF issues.

   • SYSML2-80 Reflective SysML abstract syntax model has inconsistencies
   • SYSML2-182 Universal features can have many values (partially implemented in the 2023-11 release)
   • SYSML2-552 Errors in the TradeStudy domain model

   [PR #530]

Jupyter

None.

Visualization

None.

Technical Updates

1. Metamodel files. The following metamodel files have been updated.

   org.omg.sysml/model

   • SysML.uml
   • SysML_only.uml
   • KerML_only.uml
   • SysML.ecore (includes both the KerML and SysML metamodels, as used in the implementation)
   • kerml.ecore (includes just the KerML metamodel, without implementation-specific custom annotations)

   (Note that the files SysML_only_xmi.uml and KerML_only_xmi.uml have not been updated.)

   org.omg.sysml.generation

   • SysML.uml

   [PR #527]

2. Schema files. The following JSON schema files have been updated.

   org.omg.sysml/json-schema

   • KerML.json
   • SysML.json

   [PR #532]

Bug Fixes

1. Implicit redefinitions. Adds required implicit redefinitions even if a type has (other) owned redefinitions.
   [PR #525]

2023-11 - SysML v2 Pilot Implementation

This is an incremental update to the 2023-10 release. It corresponds to Eclipse plugin version 0.37.0.

Language Features

1. Requirement constraint usage bodies. Previously, assume and require declarations in a requirement were themselves syntactically treated like requirements, and, so, could have, e.g., nested subject, assume and require declarations. Howver, assume and require actually declare constraint usages, for which nested declarations specific to requirements are invalid. This has now been changed so that assume and require declarations can only have bodies consistent with regular constraint usages.
   [PR #511]

Note. Several issues related to language bug fixes, with resolutions recently approved by the KerML and SysML v2 FTFs, were already implemented in the 2023-10 release.

Model Libraries

1. KerML. Various models in the Kernel Model Libraries have been updated consistent with the resolutions to the following KerML FTF issues. (Note that some issue resolutions recently approved by the FTF, related to the model libraries that, were already implement in the 2023-10 release.)

   • KERML-38 Binary association ends always unique
   • KERML-42 Occurrences can be data values
   • KERML-43 Performances can be objects, behaviors can be structures
   • KERML-56 Universal features can have many values
   • KERML-77 Problems with IfThenElsePerformance
   • KERML-88 BaseFunctions::',' has a bad parameter declaration
   • KERML-188 DataFunctions::Min and Max should not be capitalized
   • KERML-198 Wrong documentation format for class Occurrence in Semantic Library
   • KERML-227 Documentation of features in Transfers library model is wrong

   [PR #520]

2. SysML. Various models in the Systems and Domain Model Libraries have been updated consistent with the resolutions to the following SysML v2 FTF issues. (Note that some issue resolutions recently approved by the FTF, related to the model libraries that, were already implement in the 2023-10 release.)

   • SYSML2-79 View::viewpointSatisfactions should subset viewpointChecks and checkedConstraints
   • SYSML2-83 Narrow down return types of SpatialItem::PositionOf and ::CurrentPositionOf
   • SYSML2-102 Semantic constraint for target of AssignmentActionUsage is missing
   • SYSML2-219 Action::decisionTransitions should subset Action::transitions
   • SYSML2-305 Message and flow connection ends should be occurrence usages [fully implemented]
   • SYSML2-490 Actions::acceptSubactions and sendSubactions should subset acceptActions and sendActions

   [PR #521]

   An additional change was also made consistent with the proposed resolution to the following issue, which has not yet been approved by the FTF.

   • SYSML2-182 Universal features can have many value

   [PR #522]

Backward Incompatibilities

1. Requirement constraint usages. Certain erroneous declarations in the bodies of requirement constraint usages will now be reported as syntax errors rather than validation errors. But there is no effective change in functionality.

Jupyter

None.

Visualization

Bug fixes.

Technical Updates

1. JupyterLab installer. Updated the node.js dependency to version 15.* in the Unix/MacOS install.sh script for Jupyter, so that it works with the osx-arm64 architecture (for which a 14.* binary is not available), while still remaining on Jupyter version 2.*.

Bug Fixes

1. Implicit specialization. Fixed a bug that prevented the removal of some unnecessary implicit specializations.
   [PR #514]
2. Concern usages. Corrected the improper implicit specialization of non-framed concern usages.
   [PR #514]
3. Port usages. Corrected the implementation of isComposite for port usages.
   [PR #515]
4. View rendering usages. Corrected the implicit redefinition of view rendering usages.
   [PR #517]
5. Function operation expressions. Corrected the parsing of function operation expressions, so they parse as invocation expressions, but not operator expressions.
   [PR #518]
6. Conjugated direction. Corrected the implementation of Type::directionOf for conjugation. Also updated the derivations of Type::input and Type::output.
   [PR #519]
7. Alias membership visualization. Updated the PlantUML visualization so that unnamed alias memberships are not rendered.
   [PR #516]

2023-10 - SysML v2 Pilot Implementation

This is an incremental update to the 2023-08 release. It corresponds to Eclipse plugin version 0.36.0. (There was no 2023-09 release.)

Language Features

1. New KerML validation constraints. Checks have been implemented for the following new constraints, applying to both KerML and SysML:

   • validateRedefinitionDirectionConformance – If the redefinedFeature of a Redefinition has direction in or out, then the redefiningFeature must have the same direction. If the redefinedFeature has direction inout, then the redefiningFeature must have a non-null direction.
   • validateExpressionResultExpressionMembership – An Expression must have at most one ResultExpressionMembership.
   • validateFunctionResultExpressionMembership – A Function must have at most one ResultExpressionMembership.
   • validateFeatureValueOverriding – All Features directly or indirectly redefined by the featureWithValue of a FeatureValue must have only default FeatureValues.

   [PR #504]

2. New SysML validation constraints. Checks have been implemented for the following new constraints, applying only to SysML:

   • validateAssignmentActionUsageArguments – An AssignmentActionUsage must have two argument Expressions.
   • validateAssignmentActionUsageReferent – An AssignmentActionUsage must have an ownedMembership that is not an OwningMembership and whose memberElement is a Feature.
   • validateForLoopActionUsageLoopVariable – The first ownedFeature of a ForLoopActionUsage must be a ReferenceUsage.
   • validateForLoopActionUsageParameters – A ForLoopActionUsage must have two owned input parameters.
   • validateIfActionUsageParameters – An IfActionUsage must have at least two owned input parameters.
   • validateWhileLoopActionUsage – A WhileLoopActionUsage must have at least two owned input parameters.
   • validateTriggerInvocationExpressionAfterArgument – If a TriggerInvocationExpression has kind = after, then it must have an argument Expression with a result that conforms to the type ISQ::DurationValue.
   • validateTriggerInvocationExpressionAtArgument – If a TriggerInvocationExpression has kind = at, then it must have an argument Expression with a result that conforms to the type Time::TimeInstantValue.
   • validateTriggerInvocationExpressionWhenArgument – If a TriggerInvocationExpression has kind = when, then it must have an argument Expression with a result that conforms to the type ScalarValues::Boolean.
   • validateAssertConstraintUsageReference – If an AssertConstraintUsage has an ownedReferenceSubsetting, then its referencedFeature must be a ConstraintUsage.
   • validateSatisfyRequirementUsageReference – If a SatisfyRequirementUsage has an ownedReferenceSubsetting, then its referencedFeature must be a RequirementUsage.

   [PR #506]

3. Feature values on connections. The textual notation now supports declaring connection usages and interface usages with feature values:
   abstract connectionc1;
   abstract connectionc2 = c1; // Previously did not parse.
connectionc3 = c1connecta to b; // Previously did not parse.

   [PR #505]

4. View renderings. The notation for a view rendering usage has been extended to allow the rendering to be defined locally within the containing view, rather than just allowing rendering by reference.

   render renderingname : Def [m] ... ;

   The previous notation renderr; then effectively becomes a shorthand for render rendering referencesr;.

   [PR #505]

Model Libraries

Various library models have been updated to correct violations of new KerML validation constraints, as reported in the following KerML and SysML v2 FTF issues. Note, however, that the resolutions of these issues have not yet been approved by the FTFs and, therefore, are subject to change.
[PR #504]

KerML Issues

• KERML-182 Update Kernel Semantic Library for validateRedefinitionDirectionConformance
• KERML-184 Update Kernel Model Libraries for validateFeatureValueOverriding constraint
• KERML-186 Update semantic model of invariants for validateExpressionResultExpressionMembership constraint

SysML v2 Issues

• SYSML2-491 KerML constraint requires updates to Systems Library models
• SYSML2-492 KerML constraint requires updates to Domain Library models

Backward Incompatibilities

1. Validation constraints. The newly implemented validation constraints (particularly validateRedefinitionDirectionConformance and validateFeatureValueOverriding) may cause some models that previously passed validation to now fail.

Jupyter

None.

Visualization

1. PlantUML
   None.

2. Tom Sawyer
   None.

Technical Updates

None.

Bug Fixes

Bugs reported in the following KerML and SysML v2 issues have been fixed (or mitigated) in this release. Note, however, that the resolutions to these issues have not yet been approved by the FTFs and, therefore, are subject to change.

KerML Issue

• KERML-154 Directed features inherited from a conjugated type not handled properly

[PR #504]

SysML v2 Issues

• SYSML2-495 Textual notation BNF for TriggerExpression is wrong
• SYSML2-497 validateTriggerInvocationExpressionAfterArgument constraint is too strong
• SYSML2-498 validateTriggerInvocationExpressionWhenArgument constraint is wrong
• SYSML2-499 Assignments parsed without a target will fail validateAssignmentActionUsageArguments
• SYSML2-500 The derivation of AssignmentActionUsage::referent is wrong

[PR #506]

2023-08 - SysML v2 Pilot Implementation

This is an incremental update to the 2023-07 release. It corresponds to Eclipse plugin version 0.35.0.

Language Features

None.

Model Libraries

None.

Backward Incompatibilities

None.

Jupyter

None.

Visualization

1. PlantUML
   None.

2. Tom Sawyer
   None.

Technical Updates

None.

Bug Fixes

1. Cause and Effect Library .project.json file. Resolves OMG issue SYSML2-78 by renaming sysml.library/Domain Libraries/Cause and Effect/.proj.json to .project.json.
   [PR #497]
2. Derivation of AnalysisCaseUsage::resultExpression. Corrects the derivation computation for AnalysisCaseUsage::resultExpresson.
   [PR #498]
3. Defaults for kind properties. Corrects the default values used when serializing to XMI the kind property of various membership relationships.
   [PR #499]

2023-07 - SysML v2 Pilot Implementation

This is an incremental update to the 2023-02 release. It corresponds to Eclipse plugin version 0.34.0.

Note: This is the first release since 2023-02.

Language Features

1. Validation constraints. Most previously unimplemented validation constraints from the Beta 1 versions of the KerML and SysML specifications have now been implemented.
   [PR #486] [PR #487]

Model Libraries

None.

Backward Incompatibilities

1. Validation. Some of the newly implemented validation constraints are already automatically satisfied when a model is parsed from the textual notation. However, the other constraints may cause some models that previously passed validation checking to now fail with errors.

Jupyter

1. %help command. A new %help "magic" command has been added to the Jupyter implementation. Without an argument, this command prints a list of all available magic commands. If given a command name (with or without the initial %) as its argument, it prints the help information for that command (i.e., %helpcmd produces the same result as %cmd -h).
   [PR #493]

Visualization

1. PlantUML
   See Bug Fixes.

2. Tom Sawyer
   None.

Technical Updates

None.

Bug Fixes

1. Rendering of "initial" feature values (PlantUML). Removes the rendering of an unnecessary = along with :=.
   [PR #484]
2. Rendering of feature chains (PlantUML). Corrects the rendering of feature chains at then ends of successions in behavioral diagrams.
   [PR #485]
3. Expression evaluation. Corrects the implementation of integer division and unary Real operator evaluation.
   [PR #488]
4. Derived value computation. Corrects the computation of derived values of various properties.
   [PR #490]
5. Implicit specialization. Corrects the adding of an implicit specialization for declarations that have circular owned specializations.
   [PR #491]
6. Transition usages. Corrects a problem with the setting of the source of a transition usage that could cause spurious warning messages.
   [PR #492]
7. End features. Corrects the implicit redefinition of an end feature whose owner specializes a feature chain.
   [PR #494]
8. Analysis cases. Corrects the computation of the derived value of the resultExpression property for AnalysisCaseDefinitions and AnalysisCaseUsages.
   [PR #495]

2023-02 - SysML v2 Pilot Implementation

This is an incremental update to the 2023-01 release. It corresponds to Eclipse plugin version 0.33.0.

(Note: This is the first public release since 2022-12. There was no public release of 2023-01.)

Language Features

None.

(For Language Feature updates since 2022-12, see the 2023-01 release notes.)

Model Libraries

See Bug Fixes.

Backward Incompatibilities

None.

Jupyter

None.

Visualization

1. PlantUML

   • Perform action usages and exhibit action usages are rendered using the <<perform>> and <<exhibit>> keywords (rather than <<perform action>> and <<exhibit state>>) if the usages have no declared name or short name, but have a reference subsetting.
     [PR #469]

2. Tom Sawyer
   None.

Technical Updates

1. Abstract syntax files. All abstract syntax files have been updated to the 2023-02 baseline, consistent with the latest revised submission to OMG. Changes from 2023-01 are mostly updates to element documentation and addition of OCL constraints, plus two changes to OCL operations:

   • Correction of the return type of ActionUsage::inputParameter from Object to Feature.
   • Addition of the operation FeatureChainExpression::sourceTargetFeature.

   [PR #475]

2. Normative XMI files. Two new QVT transformations have been added to generate .uml files supporting the creation of the normative .xmi files for the KerML and SysML abstract syntax, as delivered in the latest submission to OMG.

   • SysML_xmi.uml – Combined KerML and SysML abstract syntax, but with all levels of packaging from the original MOF model.
   • KerML_only_xmi.uml – Only KerML abstract syntax, with all levels of packaging from the original MOF model.
   • SysML_only_xmi.uml – Only SysML abstract syntax, with all levels of packaging from the original MOF model. Cross-references KerML elements from KerML_only_xmi.uml.

   [PR #473]

Bug Fixes

1. UseCase::includedUseCases. Changed the subsetting of UseCases::UseCase::includedUseCases from subUseCases to enclosedPerformances. This was necessary because includedUseCases is referential (it is subsetted by IncludeUseCaseUsages, which are always referential) and subUseCases is composite.
   [PR #471]
2. Case::obj. Changed the subject of Case::obj to default to Case::result, rather than be bound it. Changed the subject of AnalysisCases::obj to override this default with a binding.
   [PR #474]
3. Empty subjects. Corrects a bug that caused empty subjects to sometimes still be shown when visualized using PlantUML in Juptyer Lab.
   [PR #477]
4. Highlighting. Fixes the highlighting of string, number and "comment" (note) tokens per Xtext configuration for the KerML and SysML editors.
   [PR #478]
5. Validation cases. Resolved "TODO" comments in various validation case models.
   [PR #479]
6. Index expressions. Fixes a bug in the implicit subsetting of index expressions that could cause errors in subsequent references from feature chaining expressions.
   [PR #480]

2023-01 - SysML v2 Pilot Implementation

This is an incremental update to the 2022-12 release. It corresponds to Eclipse plugin version 0.32.0.

(Note: This is an SST-internal release. There is no public release planned for 2023-01.)

Language Features

1. Index expressions. The bracket notation ...[...] for index expressions has been replaced with a new notation ...#(...) (parentheses are required). The bracket notation continues to be used for constructing quantities with units (e.g., 10.0[km]).

   attribute list [*] ordered = ("a", "b", "c");
   attribute a = list#(1); // value is "a"
   attribute b = list#(2); // value is "b"
   
   attribute arr : Collections::Array {
     :>> dimensions = (2, 3);
     :>> elements = ("a", "b", "c",
                     "x", "y", "z");
   }
   attribute c = arr#(1,3); // value is "c"
   attribute y = arr#(2,2); // value is "y"
   

   [PR #466]

2. Timeslices and snapshots. The abstract syntax has been simplified for occurrence usages that are time slices and snapshots, eliminating the concept of a "portioning feature". The textual notation is unchanged, but now time slices and snapshot usages implicitly subset the timeSlices or snapshots features (respectively) of each occurrence definition by which they are explicitly defined, if any, or, otherwise, the occurrence definition or usage in which they are nested.

   occurrence def AircraftFlight {
       // Implicitly subsets "timeSlices" of AircraftFlight.
       timeslice occurrence inAir;
   }
   
   // Implicitly featured by AircraftFlight.
   // Implicitly subsets "timeSlices" of AircraftFlight.
   timeslice occurrence preFlight : AircraftFlight;
   

   [PR #454]

Model Libraries

1. Deterministic UUIDs. Implemented the generation of deterministic, named-based (version 5) UUIDs as the elementIds for standard model library elements with a non-null qualifiedName.
   [PR #457]

Kernel Semantic Library

2. BaseFunctions. Added an abstract function for #.
   [PR #466]
3. SequenceFunctions and CollectionFunctions. Changed the specializations of [ to corresponding specializations of #.
   [PR #466]
4. StatePerformances. Added the feature incomingTransitionTrigger to StatePerformance, whose value is the MessageTransfer accepted to trigger a transition into a StatePerformance. (This is inherited by StateAction in SysML.)
   [PR #455]

Systems Model Library

5. Geometry. Simplified the SpatialItems model to eliminate the need for CompoundSpatialItem. Now, any SpatialItem with one or more componentItems is considered to be a compound union of those items, while a SpatialItem without any compoundItems occurs on its own, separately from its subitems.
   [PR #468]
6. Quantities and Units.
   • Added definitions for curved definitions for curved spatial coordinate frames (3D spherical, cylindrical and planetary) and associated vector quantities in addition to existing Cartesian frames and vectors.
     [PR #406]
   • Added a universalCartesianSpatial3dCoordinateFrame singleton to be used as a default coordinate frame (similar to the Time::universalClock singleton).
     [PR #406]
   • Added a transform calculation definition to VectorCalculations, which transforms a VectorQuantityValue from a source to a target CoordinateFrame.
     [PR #406]
   • Added models for TensorCalculations and MeasurementRefCalculations.
     [PR #467]

Backward Incompatibilities

1. Bracket notation. The following validation checks have been added, to catch previous uses of the bracket notation for indexing:

   • KerML. A warning whenever the bracket notation is used: "Use #(...) for indexing".
   • SysML. A warning when the bracket notation is used and the second argument is not a measurement reference: "Should be a measurement reference (unit)".

   [PR #466]

2. Vector quantities and coordinate frames. A consistent naming convention has been adopted for the names of vector and coordinate frame types and features in library packages Quantities.sysml, MeasurementReferences.sysml and ISQSpaceTime.sysml. As a result, some names of existing elements have changed. The following is an example of successive levels of specialization:

   • VectorQuantityValue, ThreeVectorValue (from KerML)
     • '3dVectorQuantityValue' (alias ThreeDVectorQuantityValue)
       • Position3dVector
         • CartesianPosition3dVector
         • CylindricalPosition3dVector
         • SphericalPosition3dVector
         • PlanetaryPosition3dVector

   [PR #406]

Jupyter

None.

Visualization

1. PlantUML
   None.

2. Tom Sawyer
   None.

Technical Updates

1. Abstract syntax files. The following UML abstract syntax model files are now available in the org.omg.sysml/model directory, reflecting the normative metamodel URIs that will be used for the OMG submission.

   • KerML_only.uml – Contains just the KerML abstract syntax metaclasses, all in a single flat package named kerml.
     URI: https://www.omg.org/spec/KerML/20230201
   • SysML_only.uml – Contains just the SysML abstract syntax metaclasses, all in a single flat package named sysml, referencing KerML elements from KerML_only.uml.
     URI: https://www.omg.org/spec/SysML/20230201
   • SysML.uml – Contains the combined SysML and KerML abstract syntax metaclasses (as before), all in a single flat package named sysml.
     URI: https://www.omg.org/spec/SysML/20230201

   [PR #452]

2. ECore metamodel. Since the Ecore metamodel SysML.ecore is generated from SysML.uml, the sysml EPackage from it is now registered using the URI https://www.omg.org/spec/SysML/20230201 (rather than http://www.omg.org/spec/SysML/2.0, as it has been previously).
   [PR #452]

3. XMI editor features. A omg.org.sysml.editor.feature has been created for the omg.org.sysml.edit and omg.org.sysml.editor plugins introduced in the last release, and this new feature has been added to omg.org.sysml.site for the Eclipse installation.
   [PR #453]

Bug Fixes

1. ControlPerformances. Constrained the earlier/later occurrences of DecisionPerformance::outgoingHBLink/MergePerformance::incomingHBLink to be the performance.
   [PR #456]
2. Links and Transfers. Made the following read-only: Link::participant, BinaryLink::source/target, Transfer::isInstant, FlowTransfer::isMove/isPush.
   [PR #459]
3. Exponential operator. Implemented ^ as an exponential operator for model-level evaluable expression evaluation.
   [PR #460]
4. ItemFlows and FlowConnectionUsages. Corrected the implicit specialization for ItemFlows and FlowConnectionUsages.
   [PR #461]
5. ActionUsages. Corrected the implicit specialization for an ActionUsage as an enclosedPerformance.
   [PR #462]
6. StateActions. Corrected the subsettings of StateAction::entryAction, exitAction and doAction.
   [PR #463]
7. Requirements. Made RequirementCheck::assumptions, constraints, subrequirements and concerns all composite. Also corrected various specializations of Actions::subactions that should have been composite.
   [PR #464]
8. Occurrences.
   • Made Occurrence::self subset spaceTimeCoincidentOccurrences.
     [PR #465]
   • Made Occurrence::spaceTimeCoincidentOccurrences subset timeCoincidentOccurrences (and other related changes).
     [PR #470]

2022-12 - SysML v2 Pilot Implementation

This is an incremental update to the 2022-11 release. It corresponds to Eclipse plugin version 0.31.0.

Language Features

KerML

1. Elements. The Element metaclass is now abstract in the Root abstract syntax. The element notation has therefore been removed from KerML.
   [PR #445]
2. Relationships. The Relationship metaclass is now abstract in the Root abstract syntax. The relationship notation has therefore been removed from KerML.
   [PR #445]
3. Dependencies. Dependency has been added to the Root abstract syntax. The concrete syntax is the same dependency notation as is already in SysML.
   [PR #445]

KerML and SysML

4. Effective names. Effective naming has been extended to short names. If both the declared name and short name of a feature are empty, but it has a naming feature (e.g., a feature it redefines), then it will take both its name and short name from the naming feature.

   part def A {
       attribute <short> longName;
   }
   part def B :> A {
       // This attribute takes both the name "longName" and
       // the short name "short" from its redefined feature.
      attribute redefines longName;
   }
   

   [PR #445]

Model Libraries

Kernel Semantic Library

1. KerML. The reflective KerML model has been updated for abstract syntax changes.
   [PR #445]
2. Occurrences and Performances. Various features related to spatial and temporal modeling associations in the Occurrences and Performances models have been marked as inverses (for example successors and predecessors in Occurrences are inverse features, related to the HappensBefore association). Certain conditions have also been moved from associations to these features.
   [PR #442 and 451]

Systems Model Library

3. SysML. The reflective SysML model has been updated for a small abstract syntax correction.
   [PR #445]
4. StandardViewDefinitions. The number of view definitions in the StandardViewDefinitions package has been reduced from 16 to 9.
   [PR #444]

Backward Incompatibilities

1. Keywords. Removed from KerML: element relationship
   [PR #445]
2. Effective names. The (non-derived) shortName and name properties of Element have been renamed to declaredShortName and declaredName. The (derived) effectiveName property has been renamed to name, and a new, derived shortName property has been added. The property name should be used instead of effectiveName when, e.g., querying for an element using the API.
   [PR #445]
3. Multiplicity. The derivation of the Type::multiplicity property in the abstract syntax has been changed to only select from the owned members of the Type. This means the property will only have a value if the Type has an explicitly declared multiplicity, but not for an implicitly "inherited" multiplicity. (The new utility method FeatureUtil.getMultiplicityOf(Type) implements the previous derivation computation for multiplicity.)
   [PR #448]

Jupyter

None.

Visualization

1. PlantUML

   • Short names. Short names (if not empty) are now shown in textual declarations rendered in compartments.
     [PR #440]
   • XMI visualization. The XMI content of a .sysmlx files can now be visualized by opening it in a basic editor in Eclipse.
     [PR #449]

2. Tom Sawyer
   None.

Technical Updates

None.

Bug Fixes

1. LiteralBoolean. The implemented default for a LiteralBoolean value was created from true to the EMF-generated false.
   [PR #446]
2. Conditional succession. The implicit specialization for TransitionUsages used as conditional succession in action models has been to be the new Action::decisionTransition feature, which is correctly typed by DecisionTransition.
   [PR #447]
3. Connections (PlantUML). Corrected the rendering of connections to redefined features.
   [PR #439]
4. Feature chains (PlantUML). Corrected the rendering of feature chains that start with subsetting or redefining features.
   [PR #443]
5. Feature values (PlantUML). Corrected the rendering of feature values that don't have an = in the textual notation.
   [PR #450]