LangPy 0.1.3

Write Python code using keywords in your native language

LangPy

Write Python in your native language 🌍

LangPy is a lexical layer over Python that lets you write code using keywords in human languages, without changing Python's behavior.

# ejemplo.pyes (Spanish)
definir saludar(nombre):
    si nombre == "Ana":
        imprimir("Hola Ana")
    sino:
        imprimir("Hola", nombre)

saludar("Luis")

$ langpy ejemplo.pyes
Hola Luis

Why LangPy?

LangPy makes Python more accessible to non-English speakers by allowing you to use natural language keywords while keeping everything else exactly the same.

What LangPy IS ✅

• A lexical transpiler that translates keywords to Python
• 100% compatible with Python libraries and tools
• Zero runtime overhead - executes as native Python
• Easy migration path back to pure Python

What LangPy is NOT ❌

• NOT a new programming language
• NOT a custom interpreter or VM
• NOT translating error messages or APIs
• NOT changing Python's semantics

If something crosses these boundaries, it's out of scope.

Quick Start

Installation

Requirements: Python 3.10+

pip install langpy

Your First Program

Create a file hello.pyes:

definir main():
    nombre = "World"
    imprimir(f"Hello {nombre}!")

main()

Run it:

langpy hello.pyes

That's it! LangPy transpiles your code to standard Python and executes it immediately.

Supported Languages

Language	Extension	Keywords Example
Spanish	.pyes	definir, si, sino, imprimir
Portuguese	.pypt	definir, se, senao, imprimir
French	.pyfr	definir, si, sinon, imprimer

The language is determined solely by the file extension. No flags or configuration needed.

Real-World Example

LangPy works seamlessly with local imports and external libraries.

operations.pyes

definir suma(a, b):
    retornar a + b

definir resta(a, b):
    retornar a - b

main.pyes

desde operations importar suma, resta
importar numpy como np

definir analizar_datos():
    # Use your functions
    resultado = suma(10, 5)
    imprimir(f"Suma: {resultado}")

    # Use any Python library
    datos = np.array([1, 2, 3, 4, 5])
    imprimir(f"Media: {np.mean(datos)}")

analizar_datos()

Run it:

langpy main.pyes

How It Works

.pyes / .pypt / .pyfr file
        ↓
tokenize (Python stdlib)
        ↓
keyword replacement
        ↓
untokenize
        ↓
execute with Python VM

Key Design Principles

• Only NAME tokens are translated (keywords)
• Strings and comments remain unchanged
• Attribute names are preserved (obj.method)
• No custom AST or parser
• If Python can't tokenize it, neither can LangPy

CLI Usage

Execute directly

langpy script.pyes

Transpile to Python

langpy --transpile script.pyes

This generates standard .py files that you can run with python.

Force overwrite

langpy --transpile --force script.pyes

Get help

langpy --help
langpy --version

Project Status

Version: 0.1.3

• ✅ Stable transpilation core
• ✅ Language lexicons defined
• ✅ Fully functional CLI
• ✅ Comprehensive test suite
• ✅ Clear project scope

Contributing

LangPy's lexicon system is modular, making it easy to add new languages without modifying the core. Want to add your language? We'd love to have you contribute!

License

MIT

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Made with ❤️ for the global Python community