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30 lines
764 B
30 lines
764 B
6 years ago
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/*
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* Copyright (c) Facebook, Inc. and its affiliates.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*/
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#include <iostream>
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#include <memory>
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// just a struct
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struct A {
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int f;
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~A() {}
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};
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// a function that returns an object, here a unique_ptr
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std::unique_ptr<A> return_object() { return std::unique_ptr<A>(new A()); }
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int main() {
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// the compiler creates a C++ temporary to hold the result
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// of the function call
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const A& a_ref = *return_object();
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// the lifetime of the temporary is only the expression
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// above, so the pointer inside a_ref has been deleted
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// by unique_ptr's destructor
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std::cout << a_ref.f; // a_ref is garbage now; boom.
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return 0;
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}
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