Errors

Solutions are marked by "⇨", optionally also with a target audience:

• MMT shell: for users of the shell interface, i.e. of java -jar mmt.jar
• API: for users of the API. There's a quickstart tutorial for API users if you haven't read that yet.

"no backend available that is applicable to "

Common reasons:

The archive declaring the element referenced by …

• … has not been loaded
  • ⇨ MMT shell: archive add <archive-path>
  • ⇨ API: ctrl.addArchive(…), see the tutorial
• … has not been built before
  • ⇨ MMT shell: archive add <archive-path>, build archiveID scala-bin, build archiveID mmt-omdoc.
    
    • TODO: Link to document explaining build steps of archives](https://github.com/UniFormal/uniformal.github.io/wiki/Issues#documentation-on-how-to-build-archives-w-or-wo-scala-Sources)
    • TODO: Link to documentation explaining where the archiveID comes from and which common ones there are (e.g. MMT/urtheories, …), the tutorial has an explanatory comment in the source code. Maybe expand that as a page on its own?
  • ⇨ API: TODO???
• … has been built, but with errors (or errors from transitive dependencies)
  • ⇨ MMT shell: closely inspect the errors, start with the first one!
  • e.g. if you references theory X { a: N } where N is not (obviously) not found.
  • e.g. if you references theory Y { include X } where X had errors building
• … has been built with another commit/branch/version of MMT
  • ⇨ MMT shell: build as above in step "has not been built before". If you want to be double sure, clean via build archiveID -Scala-bin and build archiveID -mmt-omdoc before the equivalent commands without -.
• … has been built with another Scala version than the current one
  • ⇨ rebuild as above.
    TODO How to be sure which Scala version is in use?

"invalid object", "semantic object not found"

The errors looks similar to

Exception in thread "main" invalid object (semantic object not found): scala://lf.mmt.kwarc.info?NormalizeCurrying
	at info.kwarc.mmt.api.symbols.RuleConstantInterpreter.$anonfun$createRule$2(RuleConstant.scala:59)
	at scala.Option.getOrElse(Option.scala:138)

• ⇨ Ensure you added all necessary extensions, most notably the LF plugin:

  import info.kwarc.mmt.lf
  ctrl.extman.addExtension(new lf.Plugin())

• ⇨ Ensure you loaded all necessary archives, most notably MMT/urtheories, MitM/Foundation
  TODO: Link on how to load archives.
• ⇨ Ensure all loaded archives have been built with the same Scala, Java and MMT version you are using
  ⇨ Clean and rebuild all those archives on the MMT shell (started with the Java you're using) via build archiveID -scala-bin, build archiveID -mmt-omdoc, build archiveID scala-bin, build archiveID mmt-omdoc.
  TODO: Link to page explaining archive building.