dau_driver._lazy

Import a package’s exports on first use.

Every model in this stack is a ccflow model, and importing ccflow imports csp, pandas and the rest of its stack: about 0.9 s. A package whose __init__ imports its model modules therefore pays all of it just to be imported – including when hydra’s searchpath plugin imports the config package to discover what is installed, which is the slow step in composing a registry and wants none of those names.

So a package declares which submodule provides each exported name and this builds the __getattr__ that imports the one submodule the name needs. The names stay importable exactly as before, and a type checker reads them from the TYPE_CHECKING block the package keeps beside the declaration.

Functions

lazy_exports(package, exports) → tuple[collections.abc.Callable[[str], object], list[str]]

A module __getattr__ and __all__ for {submodule: names}.

Module Contents

dau_driver._lazy.lazy_exports(package: str, exports: dict[str, tuple[str, ...]]) → tuple[collections.abc.Callable[[str], object], list[str]]

A module __getattr__ and __all__ for {submodule: names}.

Returns both so the two cannot disagree: a name exported by nothing is not reachable, and a name declared here and missing from its submodule raises on first access rather than at import – which is what the package’s lazy-export guard test turns back into an import-time error.