Alan IF IDE

Editor tooling for the Alan interactive-fiction language — syntax highlighting, navigation, real compiler diagnostics, formatting, and one-click Play, powered by a language server built with Xtext.

Alan IF, not the M-industries Alan application platform — same name, different language. This extension is for the interactive-fiction Alan.

Features

• Syntax highlighting for .alan and .i files.

• Document outline — classes, instances, additions, events, imports, verbs, syntax, scripts and synonyms, nested and with distinct icons.

• Go to Definition (F12) — across files, and aware of what a name means. A loop variable resolves to its for each rather than to an instance elsewhere that shares the name, and this resolves to the class or instance you are inside. Everything else resolves by name across the project — right for classes and instances, whose names are global in Alan — and works from isa, locate, describe, exits and the rest.

• On a verb, Go to Definition shows what decides its behaviour: the syntax that says how the player phrases it, then each class down the hierarchy that overrides it, ending where you are. In Alan's own lookup order, instead of every declaration of that name at once.

• Find All References (Shift+F12) — scoped to agree with Go to Definition: inside a loop, that loop's uses; outside it, the global's. On a verb it still lists every implementation, which is what that question means.

• Occurrences of the name under the cursor are highlighted, the declaration marked differently from the uses.

• Compiler diagnostics — the real Alan compiler's errors, shown in-editor for a whole multi-file adventure. It compiles the main file and routes each error back to the file it came from, so errors surface in your .i imports too.

  

• Play (▶) — compile the adventure and launch it in an integrated terminal, from the editor title bar, the status bar, or the context menu.

  

• Format Document — a structure-aware indenter that takes indentation from real block nesting, with optional keyword-case normalization. Multi-line strings move as rigid blocks and are never reflowed internally.

  

The Alan compiler is the source of truth for diagnostics; the language server provides the ergonomics — navigation, outline, and formatting.

Requirements

Java is included. The language server runs on the JVM, but the build for your platform ships with its own trimmed Java runtime — you do not need to install a JDK. If you would rather use your own, point alanif.java.home at it. (The platform-neutral build carries no runtime and falls back to JAVA_HOME or java on your PATH.)

To get diagnostics and Play you also need the Alan toolchain:

Without them, editing features still work — diagnostics are simply skipped.

Settings

You should not need to set the paths: leave them empty and the tools are found automatically. Clearing one always returns to that automatic search.

Knowing whether it works

While an Alan file is open, the language status bubble (the {} beside the language mode in the status bar) lists what the extension found:

Compiler 3.0beta8     ~/alan/bin/alan — PATH
Interpreter 3.0beta8  ~/alan/bin/arun — next to the compiler
Java 21               from the bundled runtime

If something is missing, a warning appears in the status bar instead — click it, or run Alan IF: Check Setup, to see all three at once and fix any of them. There is also Alan IF: Locate Alan Compiler… to browse for the compiler, and the same for the interpreter.

A note on .i files

Alan uses .i for imported source. That extension is contested — C toolchains claim it too — so this extension sets a workspace default associating *.i with Alan. If you also edit C .i files, override files.associations for that workspace.

Source and issues

Source, build instructions and issue tracker: github.com/thoni56/alan-if-ide. It is the successor to the older Eclipse-RCP AlanIDE.

License

MIT © Thomas Nilefalk.