Liakos (Rust)

A Rust port of the liakos-language tree-walking interpreter — a Monkey-style language with let, fn, closures, if/else, return, integers, booleans, strings, arrays, and hash maps.

Features

• REPL (Read-Eval-Print Loop)
• Primitive types: int, bool, string
• Data structures: arrays ([]) and hash maps ({})
• Arithmetic / comparison: + - * / < > == !=
• let bindings, if/else, return
• First-class & higher-order functions, closures, lexical scoping, recursion
• Built-ins: len, first, last, rest, push, print
• Pratt parser with proper operator precedence

Build & Run

cargo build --release

# REPL
cargo run

# Run a .liakos file
cargo run -- examples/main.liakos

REPL example

>> let add = fn(a, b) { return a + b; };
>> add(2, 3);
5
>> let fib = fn(n) { if (n < 2) { n } else { fib(n-1) + fib(n-2) } };
>> fib(10);
55

Tests

cargo test

Layout

File	Purpose
src/token.rs	Token type enum and keyword lookup
src/lexer.rs	Source → token stream
src/ast.rs	AST as Statement / Expression enums
src/parser.rs	Pratt parser
src/object.rs	Runtime object enum + hash keys
src/environment.rs	Lexical environments (Rc<RefCell<...>>)
src/evaluator.rs	Tree-walking interpreter
src/builtins.rs	Built-in functions
src/repl.rs	Interactive REPL
src/runner.rs	File runner
src/main.rs	CLI entry point