py5

A minimalist Python interpreter written in Rust.

Features

• Basic syntax: variables, expressions, conditionals, loops, functions
• Data structures: lists, dicts, tuples
• Object-oriented: classes, __init__, self, bound methods, inheritance
• Exception handling: try/except/raise
• Standard library: sys, os, time, json, math
• Module system: import/from import (via PYTHONPATH)
• Others: f-strings, decorators, generators

Build and Run

cargo build --release
cargo run -- py/basic.py

Note: The -- separator is required to pass arguments to the script.

Testing

./test.sh

Individual test files:

cargo run -- py/basic.py
cargo run -- py/oop.py
cargo run -- py/magic.py
cargo run -- py/io.py
cargo run -- py/inherit.py
cargo run -- py/args.py
cargo run -- py/unpack.py
cargo run -- py/adv_oop.py
cargo run -- py/modern.py
cargo run -- py/test_stdlib.py
cargo run -- py/test_path.py
cargo run -- py/typed_annotation.py

Module import tests:

PYTHONPATH=./py/import cargo run -- py/import/main_import.py
PYTHONPATH=./py/pkg cargo run -- py/pkg/main_pkg.py

Architecture

src/main.rs      → entry point
src/lib.rs      → run_file(): lex → parse → eval
src/lexer.rs   → tokenizer
src/parser.rs  → AST parser
src/eval.rs    → evaluator
src/value.rs   → values and environment
src/natives.rs  → built-in modules
py/            → Python test scripts

Dependencies

No external crate dependencies ([dependencies] is empty).