Kanso Language Extension for VS Code

This extension provides rich language support for Kanso smart contract development.

Features

Enhanced Syntax Highlighting

• Semantic Highlighting: Goes beyond basic syntax coloring to provide contextual highlighting
• Contract Attributes: Special highlighting for #[storage], #[event], #[create] attributes
• Symbol Distinction: Different colors for declarations vs usage, imports vs local symbols

Intelligent Code Completion

• Context-Aware Suggestions: Auto-complete based on current contract structure
• Kanso Keywords: Snippets for let, let mut, fn, ext fn, require!
• Contract Constructs: Templates for common patterns like storage structs and event definitions
• Field Access: Auto-complete struct fields when accessing State.
• Function Suggestions: Distinguish between external and internal functions

Real-time Error Detection

• Semantic Analysis: Catch errors beyond basic syntax issues
• Undefined References: Detect undefined functions, variables, and imports
• Type Validation: Smart contract specific constraints and validations
• Import Validation: Verify imported symbols exist in referenced modules

Configuration Options

Configure the extension through VS Code settings:

{
  "kanso.server.path": "kanso-lsp",
  "kanso.semanticHighlighting.enabled": true,
  "kanso.completion.enabled": true,
  "kanso.diagnostics.enabled": true
}

Commands

• Kanso: Restart Language Server - Restart the language server for development
• Kanso: Show Language Server Output - View language server logs for debugging

Installation

1. Install this VS Code extension
2. Open a .ka file to activate the language support

The Kanso Language Server is automatically built and packaged with the extension - no separate installation required!

Requirements

• VS Code 1.100.0 or higher
• Go 1.24+ (only needed if building from source)

Example

contract ERC20 {
  use std::evm::{sender, emit};
  
  #[storage]
  struct State {
    balances: Slots<Address, U256>
  }
  
  #[event]
  struct Transfer {
    from: Address,
    to: Address, 
    value: U256
  }
  
  ext fn transfer(to: Address, amount: U256) -> Bool {
    let balance = State.balances[sender()];
    require!(amount <= balance, "Insufficient balance");
    
    State.balances[sender()] -= amount;
    State.balances[to] += amount;
    
    emit(Transfer{from: sender(), to, value: amount});
    true
  }
}

With this extension, you'll get:

• Red underlines for semantic errors
• Auto-complete when typing State. shows balances
• Distinct highlighting for #[storage], #[event], function names
• Intelligent suggestions for Kanso constructs

Development

# Install dependencies
npm install

# Build LSP server and compile extension
npm run compile

# Package extension for distribution
npm run package

# Clean build artifacts
npm run clean

The build process automatically:

1. Compiles the kanso-lsp binary from the parent project
2. Copies it into the extension's bin/ directory
3. Bundles the TypeScript extension code and all dependencies into a single optimized file