Version Management and Backward Compatibility

[MaximeBaudette]

I found the following in Modelica Doc:

In a top-level class, the version number and the dependency to earlier versions of this class are defined using one or more of the following annotations:

• version = CURRENT-VERSION-NUMBER Defines the version number of the model or package. All classes within this top-level class have this version number.
• conversion ( noneFromVersion = VERSION-NUMBER) Defines that user models using the VERSION-NUMBER can be upgraded to the CURRENT-VERSION-NUMBER of the current class without any changes.
• conversion ( from (version = VERSION-NUMBER, script = "…") ) Defines that user models using the VERSION-NUMBER can be upgraded to the CURRENT-VERSION-NUMBER of the current class by applying the given script. The semantics of the conversion script is not defined.
• uses(IDENT (version = VERSION-NUMBER) ) Defines that classes within this top-level class uses version VERSION-NUMBER of classes within the toplevel class IDENT.

Maybe we should try to implement this, but we need to find out more with the syntax of the script for Dymola. I can already add when there is no conversion needed in the next version.

[dietmarw]

You can find details on the Dymola syntax with the MSL:
https://trac.modelica.org/Modelica/browser/Modelica/trunk/Modelica/Resources/Scripts/Dymola/Description.txt

Mind that there is an ongoing process to finally standardise the Modelica Script language
https://trac.modelica.org/Modelica/ticket/1443
which lead to
https://trac.modelica.org/Modelica/ticket/1622
So there is hope that there will be one standard solution that is also supported by tools other than Dymola.

[dietmarw]

In case that was not clear, for version numbers you should stick to the http://semver.org/ principle.

[MaximeBaudette]

@dietmarw
Don't worry, I got it for the version numbering :-)
Good news if the scripting is standardized... That was a jungle to find information about it otherwise.