Custom persistence - Import own languages

Hello MPS community.

Initial situation and requirements
I am currently working on a project where I am developing a standalone projectional editor for an existing language.

  • The language already has a parser implemented in Java, which I want to use for reading the files and saving them.
  • The files should be kept in their own format (custom persistence).

I have created two projects for this:

  • Project A contains the languages and the build solution for the standalone IDE.
  • Project B contains the plugin for the custom persistence, following the example of XmlSamplePersistence.

Project B imports the languages via Settings > Project Libraries.

In addition, the languages are imported in the buildscript via:
language MyLanguage
load from ./../Project A/languages/MyLanguage/MyLanguage.mpl

The plugin is successfully created and installed.
If I open my project A now, my languages are marked as read only and the message appears: Migration suspended. Some languages used in project are not deployed...

I suspect that as I imported the languages into project B, they are provided by the plugin and this will cause a collision when opened in A.
The plugin should only use the languages to build the model and not make them available.

I would be grateful for further tips. :)

Comment actions Permalink

This is normal, MPS can only load a given language once. If the language is loaded through the plugin and you then open a project containing that language, it won't be loaded again and the version from the plugin will be used. And since it's in a plugin, it is read only.

Comment actions Permalink

Thank you for your reply.

I was aiming at using my language from Project A in Project B to construct the Model.

Is there no way of importing a language into a plugin without providing the language to others?


If so I could only think of building the plugin in Project A as well to gain access to my languages.


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