foreignthon-docs/docs/index.md

ForeignThon

Write Python in any human language.

ForeignThon is a transpiler that converts .xx.py files into standard Python — keywords, builtins, and exceptions all translated into your language. The compiled output runs anywhere without ForeignThon installed.

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How it works

source.es.py  →  fpy  →  source.compiled.py  →  Python

ForeignThon uses Python's tokenize module to swap NAME tokens. Strings, comments, and f-strings are never touched. The result is identical, valid Python.

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Install

pip install foreignthon
pip install foreignthon-es   # or any other language pack

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At a glance

Feature	Description
Transpiler	Tokenizer-based, safe, unicode-aware
File format	.xx.py where xx is the language code
Errors	Shown in your language first, English below
Postfix syntax	@@ operator for SOV languages
Custom packs	Local JSON override, no PyPI needed
CLI	fpy run, fpy compile, fpy decompile, fpy new

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