Hew Language Support for VS Code

Syntax highlighting and language support for the Hew programming language — a high-performance, network-native, actor-based language.

Features

• Full syntax highlighting for Hew v0.6 constructs
• Language Server Protocol — completion, hover, definition, document symbols, semantic tokens, diagnostics (requires hew-lsp)
• Document formatting — format on save via hew fmt (requires hew CLI)
• Actor declarations — actor, receive fn, receive, init
• Supervisor trees — supervisor, child, restart, budget, strategy
• Structured concurrency — scope, launch, cancel, spawn, await
• Generators — gen fn, async gen fn, yield, cooperate
• Wire types — wire type, wire enum, field tags with @
• Traits and generics — trait, impl ... for, type parameters [T: Send]
• Pattern matching — match, =>, guards, destructuring
• All built-in types — i8–i64, u8–u64, f32, f64, bool, char, string
• String variants — regular "...", raw r"...", interpolated f"...{expr}..."
• Duration literals — 100ms, 5s, 1h
• Comments — //, /* */, /// (doc comments)
• Auto-closing pairs for brackets, braces, parentheses, strings
• Code folding and bracket matching

Example

actor Counter {
    var count: i32 = 0;

    receive fn increment() {
        self.count = self.count + 1;
    }

    receive fn get() -> i32 {
        self.count
    }
}

supervisor CounterSupervisor {
    child counter: Counter
        restart(permanent)
        budget(5, 30s)
        strategy(one_for_one);
}

fn fibonacci(n: i32) -> i32 {
    if n <= 1 {
        n
    } else {
        fibonacci(n - 1) + fibonacci(n - 2)
    }
}

fn main() -> i32 {
    let result = fibonacci(10);
    println(result);
    0
}

Installation

From VSIX (local install)

1. In the extension directory, run:

   npm run package
   

2. In VS Code, open the command palette (Ctrl+Shift+P) and run: Extensions: Install from VSIX...
3. Select the generated .vsix file

From source (development)

1. Clone this repository
2. Run npm install && npm run build:dev
3. Open this folder in VS Code and press F5 to launch the Extension Development Host

Configuration

Supported Token Scopes

License

Licensed under the Apache License, Version 2.0. See LICENSE for details.