Unable to import Arrow core classes after adding Maven dependency


Hi all, I'm having trouble adding Arrow to a Maven project created from a simple start.spring.io skeleton.

I've added Arrow core as a dependency to the POM and refreshed Maven. I can "Navigate -> Class" in the IDE and input an Arrow class such as Either, and IntelliJ finds it in arrow-core-1.0.1.jar. However, if I "import arrow.core.Either", it complains with "Unresolved reference arrow".

A similar start.spring.io skeleton using Gradle works fine. 

I've tried invalidating caches as well as removing the .idea/ directory and re-importing the project. And along the way I upgraded the Kotlin plugin from 1.5.10 to 1.6.10-RC. I'm using Intellij 2021.3 on Windows 10. 

I'm out of ideas and any help/suggestions are appreciated.



may you share the maven project you generated? You can do that via GutHub, or uploads.jetbrains.com


Done, file reference: 2021_12_14_TSRNsppPAtvJVGRy

It's a barebones start.spring.io with arrow-core added. Thanks for looking at it.


I mean the whole project sample, not only pom.xml. 

Where do you insert the import? Is it Kotlin, or Java file? 


Ah sorry, done and at 2021_12_15_4GhqMhrRgeVcJT73.

I added the import to ArrowTestApplication.kt ("import arrow.core.Either"). And here's what I get:


It is hardly related to IntelliJ IDEA. Maven does not compile the project in the command line also: https://i.imgur.com/2BU15Yi.jpg

I'd submit an issue to arrow core github: https://github.com/arrow-kt/arrow-core/issues


Just found a similar Kotlin bug: https://youtrack.jetbrains.com/issue/KT-25709#focus=Comments-27-3728739.0-0

That could be related. 

I've added Kotlin team to CC, maybe they can shed some light on that. 


Does it work if you depend on `arrow-core-jvm` instead of `arrow-core`? If yes, please file an issue to https://github.com/arrow-kt/arrow so that the maintainers of Arrow update the documentation on how to use the library from Maven.


Alexey Belkov thanks, that does indeed work! I'll file an issue with Arrow momentarily. And thanks Konstantin Annikov for getting me to the right person to solve this.


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