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Author: larryliu0820

src/README.md

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+# Why We Have a src/executorch/exir File
+
+The `src/executorch/exir` file exists primarily due to the limitations of `pip install` in editable mode. Specifically, `pip install -e .` does not recognize `<executorch root>/exir` (or any root level directory with a `__init__.py`) as a valid package module because of the presence of `<executorch root>/exir/__init__.py`. See the following GitHub issue for details: [Issue #9558](https://github.com/pytorch/executorch/issues/9558).
+
+## The Symlink Solution
+
+To work around this limitation, a symlink is used. With this symlink and this package entry in `pyproject.toml`:
+
+```toml
+[tool.setuptools.package-dir]
+...
+"executorch" = "src/executorch"
+```
+We are telling `pip install -e .` to treat `src/executorch` as the root of the `executorch` package and hence mapping `executorch.exir` to `src/executorch/exir`.
+
+This allows us to perform `pip install -e .` successfully and enables the execution of the following command:
+
+```bash
+python -c "from executorch.exir import CaptureConfig"
+```