Ado - A Minimal Programming Language

A lightweight, performant programming language that compiles to C.

File Extension: .do | Compiler: doc | Language Server: do-lsp

Features

• Simple, intuitive syntax inspired by modern languages
• Compiles to C for maximum performance with -O2 optimization
• Minimal runtime overhead
• Interactive REPL for rapid development
• Full IDE support via LSP and Tree-sitter

Language Features

• Functions with parameters and recursion
• Variables with let
• Control flow: if/else, while loops, for loops
• Arrays: implicit memory pointers via [val1, val2], len(arr), push(arr, val)
• Rich operators: arithmetic, comparison, logical
• Built-in I/O with print()
• Comments with #

IDE Features (via LSP)

• Completion - Functions, variables, keywords, snippets
• Go to Definition - Jump to symbol definitions
• Find References - Find all usages
• Hover - Type information and documentation
• Signature Help - Function parameter hints
• Rename - Symbol renaming across files
• Diagnostics - Real-time error detection
• Code Actions - Quick fixes and refactorings
• Code Lenses - Reference counts
• Formatting - Auto-format code

Quick Start

# Build compiler
./build.sh

# Set up development environment
./setup-dev.sh

# Launch IDE
./ado-edit example.do

# Or compile and run directly
./doc example.do

# Interactive REPL
./doc

Syntax

# Comment
fn factorial(n) {
  if n <= 1 {
    return 1
  }
  return n * factorial(n - 1)
}

fn main() {
  print("Factorial of 10:", factorial(10))
  
  let i = 0
  while i < 10 {
    print(i)
    i = i + 1
  }
  
  return 0
}

Build

./build.sh

Usage

# Run a file
./doc example.do

# Interactive REPL
./doc

# Run file then enter REPL
./doc -i example.do

REPL Commands

• quit - Exit REPL
• help - Show available commands
• clear - Clear the current buffer

Development Setup

Run the setup script for a complete IDE experience:

./setup-dev.sh
./ado-edit example.do

This launches Neovim with:

• LSP server (completion, diagnostics, go-to-definition)
• Tree-sitter syntax highlighting (if installed)
• Auto-formatting
• Symbol renaming

Neovim Key Bindings

Key	Action
gd	Go to definition
gD	Go to type definition
gr	Find references
K	Show hover info
<leader>rn	Rename symbol
<leader>f	Format document
<leader>ca	Code actions
<C-k>	Signature help
[d / ]d	Navigate diagnostics

Language Reference

Functions

fn name(params) { body }

Variables

let name = value

Control Flow

if condition { } else { }
while condition { }

Return

return value

I/O

print(expr1, expr2, ...)  # Print values

Operators

• Arithmetic: +, -, *, /, %
• Comparison: ==, !=, <, >, <=, >=
• Logical: and, or, not

Literals

• Integers: 42, -10
• Booleans: true, false
• Strings: "hello\nworld"

Comments

# Single line comment

Examples

See the examples/ directory:

• example.do - Comprehensive feature demo
• collatz.do - Collatz sequence calculator
• math.do - Math functions
• conditionals.do - Conditional expressions

Architecture

Source (.do) → Lexer → Parser → AST → Codegen → C → Binary
                                        ↓
                                      LSP Server

Directory Structure

.
├── doc                 # Compiler binary
├── build.sh            # Build script
├── setup-dev.sh        # IDE setup script
├── ado-edit            # Neovim launcher
├── main.c              # Main entry point
├── lexer.c/h           # Lexer
├── parser.c/h          # Parser
├── codegen.c/h         # Code generator
├── lsp/
│   └── do-lsp.py       # Language server
├── nvim/
│   └── init.lua        # Neovim config
├── tree-sitter-do/     # Tree-sitter grammar
├── vim/                # Vim syntax files
└── examples/           # Example programs

Performance

Ado compiles to optimized C code with -O2, running at near-native speed. The generated C code is clean and readable.