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36 lines
1.2 KiB
Text
36 lines
1.2 KiB
Text
Now that we've familiarized ourselves with the overloaded assignment operator
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and the move-assignment, let's once again have a look at their
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implementations for a class tt(Class), supporting swapping through its
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tt(swap) member. Here is the generic implementation of the overloaded
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assignment operator:
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verb(
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Class &operator=(Class const &other)
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{
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Class tmp{ other };
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swap(tmp);
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return *this;
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}
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)
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and this is the move-assignment operator:
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verb(
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Class &operator=(Class &&tmp)
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{
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swap(tmp);
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return *this;
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}
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)
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They look remarkably similar in the sense that the overloaded assignment
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operator's code is identical to the move-assignment operator's code once a
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copy of the tt(other) object is available. Since the overloaded assignment
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operator's tt(tmp) object really is nothing but a temporary tt(Class) object
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we can use this fact by implementing the overloaded assignment operator in
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terms of the move-assignment. Here is a second revision of the overloaded
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assignment operator:
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verb(
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Class &operator=(Class const &other)
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{
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Class tmp{ other };
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return *this = std::move(tmp);
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}
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)
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COMMENT(Demo in examples/moveassign.cc)
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