Source code for zict.func

from __future__ import annotations

from import Callable, Iterable, Iterator, MutableMapping
from typing import Generic, TypeVar

from zict.common import KT, VT, ZictBase, close, flush

WT = TypeVar("WT")

[docs] class Func(ZictBase[KT, VT], Generic[KT, VT, WT]): """Translate the values of a MutableMapping with a pair of input/output functions Parameters ---------- dump: callable Function to call on value as we set it into the mapping load: callable Function to call on value as we pull it from the mapping d: MutableMapping See Also -------- KeyMap Examples -------- >>> def double(x): ... return x * 2 >>> def halve(x): ... return x / 2 >>> d = {} >>> f = Func(double, halve, d) >>> f['x'] = 10 >>> d {'x': 20} >>> f['x'] 10.0 """ dump: Callable[[VT], WT] load: Callable[[WT], VT] d: MutableMapping[KT, WT] def __init__( self, dump: Callable[[VT], WT], load: Callable[[WT], VT], d: MutableMapping[KT, WT], ): super().__init__() self.dump = dump self.load = load self.d = d def __getitem__(self, key: KT) -> VT: return self.load(self.d[key]) def __setitem__(self, key: KT, value: VT) -> None: self.d[key] = self.dump(value) def __contains__(self, key: object) -> bool: return key in self.d def __delitem__(self, key: KT) -> None: del self.d[key] def _do_update(self, items: Iterable[tuple[KT, VT]]) -> None: it = ((k, self.dump(v)) for k, v in items) self.d.update(it) def __iter__(self) -> Iterator[KT]: return iter(self.d) def __len__(self) -> int: return len(self.d) def __str__(self) -> str: return f"<Func: {funcname(self.dump)}<->{funcname(self.load)} {self.d}>" __repr__ = __str__ def flush(self) -> None: flush(self.d)
[docs] def close(self) -> None: close(self.d)
def funcname(func: Callable) -> str: """Get the name of a function.""" while hasattr(func, "func"): func = func.func try: return func.__name__ except Exception: return str(func)