deferred_operand.py

   1 #!/usr/bin/env python3
   2
   3 # © Copyright 2021-2022, Scott Gasch
   4
   5 """This is a helper class that tries to define every __dunder__ method
   6 so as to defer that evaluation of an object as long as possible.  It
   7 is used by smart_future.py as a base class.
   8
   9 """
  10
  11 from abc import ABC, abstractmethod
  12 from typing import Any, Generic, TypeVar
  13
  14 # This module is commonly used by others in here and should avoid
  15 # taking any unnecessary dependencies back on them.
  16
  17 T = TypeVar('T')
  18
  19
  20 class DeferredOperand(ABC, Generic[T]):
  21     """A wrapper around an operand whose value is deferred until it is
  22     needed (i.e. accessed).  See the subclass :class:`SmartFuture` for
  23     an example usage and/or a more useful patten.
  24     """
  25
  26     @abstractmethod
  27     def _resolve(self, timeout=None) -> T:
  28         pass
  29
  30     @staticmethod
  31     def resolve(x: Any) -> Any:
  32         while isinstance(x, DeferredOperand):
  33             x = x._resolve()
  34         return x
  35
  36     def __lt__(self, other: Any) -> bool:
  37         return DeferredOperand.resolve(self) < DeferredOperand.resolve(other)
  38
  39     def __le__(self, other: Any) -> bool:
  40         return DeferredOperand.resolve(self) <= DeferredOperand.resolve(other)
  41
  42     def __eq__(self, other: Any) -> bool:
  43         return DeferredOperand.resolve(self) == DeferredOperand.resolve(other)
  44
  45     def __ne__(self, other: Any) -> bool:
  46         return DeferredOperand.resolve(self) != DeferredOperand.resolve(other)
  47
  48     def __gt__(self, other: Any) -> bool:
  49         return DeferredOperand.resolve(self) > DeferredOperand.resolve(other)
  50
  51     def __ge__(self, other: Any) -> bool:
  52         return DeferredOperand.resolve(self) >= DeferredOperand.resolve(other)
  53
  54     def __not__(self) -> bool:
  55         return not DeferredOperand.resolve(self)
  56
  57     def bool(self) -> bool:
  58         return DeferredOperand.resolve(self)
  59
  60     def __add__(self, other: Any) -> T:
  61         return DeferredOperand.resolve(self) + DeferredOperand.resolve(other)
  62
  63     def __iadd__(self, other: Any) -> T:
  64         return DeferredOperand.resolve(self) + DeferredOperand.resolve(other)
  65
  66     def __radd__(self, other: Any) -> T:
  67         return DeferredOperand.resolve(self) + DeferredOperand.resolve(other)
  68
  69     def __sub__(self, other: Any) -> T:
  70         return DeferredOperand.resolve(self) - DeferredOperand.resolve(other)
  71
  72     def __mul__(self, other: Any) -> T:
  73         return DeferredOperand.resolve(self) * DeferredOperand.resolve(other)
  74
  75     def __pow__(self, other: Any) -> T:
  76         return DeferredOperand.resolve(self) ** DeferredOperand.resolve(other)
  77
  78     def __truediv__(self, other: Any) -> Any:
  79         return DeferredOperand.resolve(self) / DeferredOperand.resolve(other)
  80
  81     def __floordiv__(self, other: Any) -> T:
  82         return DeferredOperand.resolve(self) // DeferredOperand.resolve(other)
  83
  84     def __contains__(self, other):
  85         return DeferredOperand.resolve(other) in DeferredOperand.resolve(self)
  86
  87     def and_(self, other):
  88         return DeferredOperand.resolve(self) & DeferredOperand.resolve(other)
  89
  90     def or_(self, other):
  91         return DeferredOperand.resolve(self) & DeferredOperand.resolve(other)
  92
  93     def xor(self, other):
  94         return DeferredOperand.resolve(self) & DeferredOperand.resolve(other)
  95
  96     def invert(self):
  97         return ~(DeferredOperand.resolve(self))
  98
  99     def is_(self, other):
 100         return DeferredOperand.resolve(self) is DeferredOperand.resolve(other)
 101
 102     def is_not(self, other):
 103         return DeferredOperand.resolve(self) is not DeferredOperand.resolve(other)
 104
 105     def __abs__(self):
 106         return abs(DeferredOperand.resolve(self))
 107
 108     def setitem(self, k, v):
 109         DeferredOperand.resolve(self)[DeferredOperand.resolve(k)] = v
 110
 111     def delitem(self, k):
 112         del DeferredOperand.resolve(self)[DeferredOperand.resolve(k)]
 113
 114     def getitem(self, k):
 115         return DeferredOperand.resolve(self)[DeferredOperand.resolve(k)]
 116
 117     def lshift(self, other):
 118         return DeferredOperand.resolve(self) << DeferredOperand.resolve(other)
 119
 120     def rshift(self, other):
 121         return DeferredOperand.resolve(self) >> DeferredOperand.resolve(other)
 122
 123     def mod(self, other):
 124         return DeferredOperand.resolve(self) % DeferredOperand.resolve(other)
 125
 126     def matmul(self, other):
 127         return DeferredOperand.resolve(self) @ DeferredOperand.resolve(other)
 128
 129     def neg(self):
 130         return -(DeferredOperand.resolve(self))
 131
 132     def pos(self):
 133         return +(DeferredOperand.resolve(self))
 134
 135     def truth(self):
 136         return DeferredOperand.resolve(self)
 137
 138     def __hash__(self):
 139         return DeferredOperand.resolve(self).__hash__()
 140
 141     def __call__(self):
 142         return DeferredOperand.resolve(self)()
 143
 144     def __iter__(self):
 145         return DeferredOperand.resolve(self).__iter__()
 146
 147     def __repr__(self) -> str:
 148         return DeferredOperand.resolve(self).__repr__()
 149
 150     def __bytes__(self) -> bytes:
 151         return DeferredOperand.resolve(self).__bytes__()
 152
 153     def __int__(self) -> int:
 154         return int(DeferredOperand.resolve(self))
 155
 156     def __float__(self) -> float:
 157         return float(DeferredOperand.resolve(self))
 158
 159     def __getattr__(self, method_name):
 160         def method(*args, **kwargs):
 161             return getattr(DeferredOperand.resolve(self), method_name)(*args, **kwargs)
 162
 163         return method