tmp/tmpj3y_pt86/{from.md → to.md}
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#### Simple assignment <a id="over.ass">[[over.ass]]</a>
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A *simple assignment operator function* is a binary operator function
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named `operator=`. A simple assignment operator function shall be a
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non-static member function.
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[*Note 1*: Because only standard conversion sequences are considered
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when converting to the left operand of an assignment operation
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[[over.best.ics]], an expression `x = y` with a subexpression x of class
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type is always interpreted as `x.operator=(y)`. — *end note*]
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[*Note 2*: Since a copy assignment operator is implicitly declared for
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a class if not declared by the user [[class.copy.assign]], a base class
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assignment operator function is always hidden by the copy assignment
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operator function of the derived class. — *end note*]
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[*Note 3*:
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Any assignment operator function, even the copy and move assignment
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operators, can be virtual. For a derived class `D` with a base class `B`
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for which a virtual copy/move assignment has been declared, the
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copy/move assignment operator in `D` does not override `B`’s virtual
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copy/move assignment operator.
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[*Example 1*:
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``` cpp
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struct B {
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virtual int operator= (int);
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virtual B& operator= (const B&);
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};
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struct D : B {
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virtual int operator= (int);
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virtual D& operator= (const B&);
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};
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D dobj1;
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D dobj2;
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B* bptr = &dobj1;
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void f() {
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bptr->operator=(99); // calls D::operator=(int)
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*bptr = 99; // ditto
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bptr->operator=(dobj2); // calls D::operator=(const B&)
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*bptr = dobj2; // ditto
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dobj1 = dobj2; // calls implicitly-declared D::operator=(const D&)
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}
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```
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— *end example*]
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— *end note*]
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