FregeIntelliJPlugin

This is the IntelliJ plugin for Frege! It provides IDE support for the Frege programming language using the Frege Language Server.

It depends on the Frege Language Server version v1.0.2 & Frege version 3.25.84.

Note 1: Make sure your Frege files are located in ./src/main/frege or in the directory stated in the environment variable FREGE_LS_SOURCE_DIR. The Frege Language Server uses the file system to resolve modules. Therefore, always use the file path relative to FREGE_LS_SOURCE_DIR as module name.

Note 2 Syntax highlighting: Open Settings -> Editor -> File Types -> Recognized File Types. Search for Haskell and add *.fr to File name patterns:

Java interoperability

Accessing Java files

If you want to access Java files along with your Frege code make sure to put the Java code in ./src/main/java or into the directory stated in the environment variable FREGE_LS_JAVA_SOURCE_DIR.

Accessing Jars

If you want to use external Jar files along with your Frege code make sure to put them under the ./lib folder or into the directory stated in the environment variable FREGE_LS_EXTRA_CLASSPATH.

Installation

We currently only support manual installation. The plugin depends on the IntelliJ Language Server Protocol support. See here to find out which IDEs are supported!

Download the latest release and install it manually using Settings/Preferences > Plugins > ⚙️ > Install plugin from disk...

Developing

Tested with gradle 8.14.3, IntelliJ IDEA 2025.1.2 and Kotlin 2.2.0.

Building the source

Use ./gradlew buildPlugin. It might take a while as it downloads many Jetbrains dependencies

Running it locally

Use ./gradlew runIde to start a new IntelliJ instance with the current version of the plugin installed.

Upgrading the Frege Language Server

1. Download the latest release tar here and replace the version in src/main/resources/fregels.
2. Change the version of Frege/FregeLS in Versions.kt, in this Readme and in gradle.properties.
3. Commit & Push
4. Run ./gradlew buildPlugin
5. Create a new GitHub Release with and upload the contents of ./build/distributions to it

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Plugin based on the IntelliJ Platform Plugin Template.