std::ios_base::operator=
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std::ios_base 
 
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ios_base::operator=
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private:
ios_base& operator=( const ios_base& );
 
 (until C++11) 
ios_base& operator=( const ios_base& );
public:
ios_base& operator=( const ios_base& ) = delete;
 
 (since C++11) 
ios_base& operator=( const ios_base& ) = delete;
The copy assignment operator is private(until C++11)deleted(since C++11): streams are not copy-assignable.
[edit] Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior | 
|---|---|---|---|
| LWG 50 | C++98 | the copy assignment operator was not specified | specified as private |