The simplest possible IntelliJ custom language plugin. Implements the Hello language, whose purpose is to exercise the features of the IntelliJ API in the simplest possible context.

Hello language

The Hello language consists of:

Strings

"Hello world!"

Symbols

x

Let expressions

let x = "Hello world!" in x

Plugin features

• Syntax highlighting
• Annotations
• Symbol references
• In-place renaming
• Code formatting
• Test fixtures

TODO plugin features

• Reference Java symbols from Hello
• Reference Hello symbols from Java (requires additional syntax, PsiReferenceContributor?)
• Run configuration that invokes Hello interpreter
• Compilation of Hello files using ASM

Building

Running 'Build -> Prepare Plugin Module 'hello' for deployment' will produce hello.jar in the base directory.

'hello.jar' can be installed with 'File -> Settings', 'Plugins', 'Install plugin from disk'.

Once you've installed the plugin, the 'test.hello' file should show up with a fancy icon with the word 'Hi' in green text.

Layout

.idea/

Intellij project files

META-INF/

Contains plugin.xml, the plugin configuration file.

resources/

Icons.

src/

Java sources.

test.hello

Once you've built and installed the plugin, this file should show up in the project tree with a special icon with the word 'Hi' in green text.