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85 lines
2.0 KiB
85 lines
2.0 KiB
3 years ago
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#!/usr/bin/env python3
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# MIT License
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#
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# Copyright (c) 2023 Eugenio Parodi <ceccopierangiolieugenio AT googlemail DOT com>
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#
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# Permission is hereby granted, free of charge, to any person obtaining a copy
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# of this software and associated documentation files (the "Software"), to deal
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# in the Software without restriction, including without limitation the rights
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# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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# copies of the Software, and to permit persons to whom the Software is
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# furnished to do so, subject to the following conditions:
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#
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# The above copyright notice and this permission notice shall be included in all
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# copies or substantial portions of the Software.
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#
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# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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# SOFTWARE.
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import weakref
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import gc
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class Obj():
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def __init__(self, v=None) -> None:
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self._v = v
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self._k = None
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if v: v.setK(self)
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def setK(self,k):
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self._k = k
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def __del__(self):
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print(f"Delete {self=} -> {self._v} {self._k}")
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k1 = Obj()
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k2 = Obj()
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k3 = Obj()
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k4 = Obj()
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k5 = Obj(k4)
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d = weakref.WeakKeyDictionary()
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def ppp(n):
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print(f"Dump: {n=}")
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print(f"{gc.get_count()}, {gc.get_stats()}, {gc.garbage}")
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for i in d:
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print(f"<*> - {i=} {d[i]=}")
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d[Obj(k1)] = "k1"
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d[Obj(k2)] = "k2"
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d[Obj(k3)] = "k3"
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ppp(1)
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del k2
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k4 = k5 = None
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gc.collect()
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ppp(2)
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k3 = None
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gc.collect()
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ppp(3)
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print("------> Inizio della seconda parte")
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k1 = Obj()
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k2 = Obj()
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k3 = Obj()
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d[k1] = weakref.ref(Obj(k1))
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d[k2] = weakref.ref(Obj(k2))
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d[k3] = weakref.ref(Obj(k3))
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print(f"{k1 in d=}")
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ppp(4)
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del k2
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gc.collect()
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ppp(5)
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k3 = k1 = None
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gc.collect()
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ppp(6)
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