SysMLv1.x: An ElementGroup used for basic Parsing Analysis model element elicitation: Example 1

The criterion is that to be a member a symbol or label of a member element must appear on the same diagram as the ElementGroup. The collected members are: a Block BlockA; a part Property partE and its typing block BlockD; a value Property valueC and its typing ValueType ValueTypeB; and an Activity ActivityF.

For real applications the display of all of this information can become unwieldy. The 'criterion' is basically redundant given that the identical Comment 'body' is shown, and the we can easily live without showing the 'size', and the 'name' is not always so useful:

The default display of all tagged values on the comment symbol for an ElementGroup can make diagrams cluttered, but you can extend it with a custom stereotype and customise the default visible tagged values.

Which BTW is why:

The Webel Parsing Analysis recipe for SysML1.x does not use the ElementGroup directly, it extends it as a user-defined Snippet stereotype with keyword «snippet» and with MagicDraw Customization.

Also:

Webel Best Practice: Do not feel obliged to use the 'name' property of an ElementGroup if you don't feel it adds value.

It's worth knowing a bit about the underlying Comment notation:

UML-2.5.1: 'A Comment is shown as a rectangle with the upper right corner bent (this is also known as a “note symbol”). The rectangle contains the body of the Comment. The connection to each annotatedElement is shown by a separate dashed line.'

Throughout this section and other tutorial trails this 'anchor' terminology will be used:

In MagicDraw/Cameo the dashed line symbol from a UML Comment or SysMLv1.x ElementGroup to an annotatedElement is called an 'anchor'.

An 'anchor' can get at nearly anything that appears in nearly any way in a diagram as a symbol, relationship label, end Property label, or compartment row label. But not every kind of candidate member element can appear on every kind of diagram. No problem:

An ElementGroup comment symbol may appear on more than one diagram type and may collect different kinds of anchored annotatedElement members from more than diagram.

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SysMLv1.x: An ElementGroup used for basic Parsing Analysis model element elicitation: Example 2

Notes

[OPTION]{OPTION} Do not feel obliged to use the 'name' property of an ElementGroup if you don't feel it adds value.

[OPTION]{OPTION} The default display of all tagged values on the comment symbol for an ElementGroup can make diagrams cluttered, but you can extend it with a custom stereotype and customise the default visible tagged values.

[TIP]{INFORMATIVE} The Webel Parsing Analysis recipe for SysML1.x does not use the ElementGroup directly, it extends it as a user-defined Snippet stereotype with keyword «snippet» and with MagicDraw Customization.

[TOOL]{INFORMATIVE} In MagicDraw/Cameo the dashed line symbol from a UML Comment or SysMLv1.x ElementGroup to an annotatedElement is called an 'anchor'.

[TIP]{INFORMATIVE} An ElementGroup comment symbol may appear on more than one diagram type and may collect different kinds of anchored annotatedElement members from more than diagram.

Snippets (quotes/extracts)

[SysML-1.6] The ElementGroup stereotype provides a lightweight mechanism for grouping various and possibly heterogeneous model elements by extending the capability of comments to refer to multiple annotated elements.

[SysML-1.6] For example, it can group elements that are associated with a particular release of the model, have a certain risk level, or are associated with a legacy design.