Python Project Skeleton

SLS_Python/.gitignore

@@ -1 +1,2 @@
 __pycache__/
+.venv/

SLS_Python/README.md

@@ -1,3 +1,42 @@
 # SLS Python
 
-This is the Python implementation for the YREA SLS interpreter.
+This directory contains a minimal Python project skeleton intended to reimplement
+functionality from the C `SLS` project found at the repository root.
+
+Layout
+- `src/sls/` — Python package with module skeletons: `lexer`, `parser`, `interpreter`, `builtin`, `repl`, and `cli`.
+- `tests/` — pytest tests (start with `test_import.py`).
+- `pyproject.toml` — project metadata and `sls` console script entrypoint.
+- `requirements-dev.txt` — developer/test tools.
+
+Quick start
+
+Create a venv and install editable package + dev requirements:
+
+```bash
+python -m venv .venv
+source .venv/bin/activate
+pip install -e SLS_Python
+pip install -r SLS_Python/requirements-dev.txt
+```
+
+Run tests:
+
+```bash
+pytest -q
+```
+
+Run the REPL:
+
+```bash
+sls repl
+```
+
+Next steps (suggested)
+- Port `lexer.c` to `src/sls/lexer.py` and add comprehensive tokenization tests.
+- Port `parser` and `interpreter` incrementally, keeping tests for parity.
+- Add CI (GitHub Actions) and type checking (`mypy`).
+
+If you want, I can now:
+- Run the tests in this environment (if you want me to configure the Python env), or
+- Start porting a specific module from the C implementation (lexer is a good first target).

SLS_Python/pyproject.toml

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+[build-system]
+requires = ["setuptools>=61.0", "wheel"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "sls-python"
+version = "0.1.0"
+description = "Python reimplementation skeleton of the SLS C project"
+authors = [ { name = "Your Name" } ]
+readme = "README.md"
+license = { text = "MIT" }
+requires-python = ">=3.10"
+dependencies = [
+    "click>=8.0"
+]
+
+[project.scripts]
+sls = "sls.cli:main"

SLS_Python/requirements-dev.txt

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+pytest
+click
+mypy
+black

SLS_Python/sls/__init__.py

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+"""sls — Python skeleton for SLS reimplementation
+
+Expose package version and small helpers here.
+"""
+
+__all__ = ["__version__", "cli"]
+
+__version__ = "0.0.1"

SLS_Python/sls/builtin.py

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+"""Builtins and native functions for SLS."""
+
+def load_builtins():
+    """Return a dict of builtin names to callables."""
+    return {
+        "print": print,
+    }

SLS_Python/sls/cli.py

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+"""Command-line entry point for SLS Python."""
+import click
+
+from . import __version__
+
+
+@click.group()
+@click.version_option(__version__)
+def main():
+    """sls: Small Lisp-like language (Python reimplementation)."""
+    pass
+
+
+@main.command()
+def repl():
+    """Start a minimal REPL."""
+    from .repl import repl_loop
+
+    repl_loop()
+
+
+@main.command()
+@click.argument("file", required=False)
+def run(file):
+    """Run an SLS source file (placeholder)."""
+    if not file:
+        click.echo("No file provided; start with `sls repl`")
+        return
+    click.echo(f"Would run: {file} (not implemented yet)")

SLS_Python/sls/interpreter.py

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+"""Interpreter module placeholder for SLS."""
+
+from typing import Any
+
+
+class Interpreter:
+    def __init__(self):
+        self.env = {}
+
+    def eval(self, ast: Any):
+        """Evaluate the AST and return a result. Not implemented yet."""
+        return None

SLS_Python/sls/lexer.py

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+"""Lexer module placeholder for SLS.
+
+Provide a Lexer class that will later be expanded to match the C implementation.
+"""
+
+from dataclasses import dataclass
+from typing import Iterator, NamedTuple
+
+
+class Token(NamedTuple):
+    type: str
+    value: str
+    lineno: int
+    col: int
+
+
+@dataclass
+class Lexer:
+    source: str
+
+    def tokenize(self) -> Iterator[Token]:
+        """Yield tokens from `source`. Currently yields a single EOF token.
+        Replace with full logic when porting the C lexer.
+        """
+        yield Token("EOF", "", 1, 0)

SLS_Python/sls/repl.py

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+"""Simple REPL for SLS skeleton."""
+
+from .lexer import Lexer
+from .parser import Parser
+from .interpreter import Interpreter
+
+
+def repl_loop():
+    interp = Interpreter()
+    print("sls-python REPL (very minimal). Type 'quit' or Ctrl-D to exit.")
+    try:
+        while True:
+            src = input("sls> ")
+            if not src or src.strip() in ("quit", "exit"):
+                break
+            # minimal echo behaviour for now
+            lexer = Lexer(src)
+            tokens = list(lexer.tokenize())
+            ast = Parser(tokens).parse()
+            result = interp.eval(ast)
+            if result is not None:
+                print(result)
+    except (EOFError, KeyboardInterrupt):
+        print()
+        print("Bye")

SLS_Python/tests/test_import.py

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+def test_import_package():
+    import sls
+
+    assert hasattr(sls, "__version__")
+    assert isinstance(sls.__version__, str)