34 lines
1.1 KiB
Plaintext
34 lines
1.1 KiB
Plaintext
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Overloaded versions of the comma and logical conjunction operators have the semantics of function calls whose sequence point and ordering semantics are different from those of the built- in versions. It may not be clear at the point of use that these operators are overloaded, and so developers may be unaware which semantics apply.
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Exception: Starting from _C++17_, the order of evaluation of the comma operator is defined and identical for the builtin and the overloaded versions. In such circumstances, the coma operator can safely be overloaded.
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== Noncompliant Code Example
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----
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#include "util.h"
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class A
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{
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public:
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UtilType getValue ( );
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UtilType setValue ( UtilType const & );
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};
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void f1 ( A & a1, A & a2 )
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{
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a1.getValue ( ) && a2.setValue ( 0 ); // Short circuiting may occur
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}
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bool operator && ( UtilType const &,
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UtilType const & ); // Noncompliant
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void f2 ( A & a1, A & a2 )
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{
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a1.getValue ( ) && a2.setValue ( 0 ); // Both operands evaluated if type returned has overloaded operator&&
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}
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----
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== See
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* MISRA C++ 2008, 5-2-11 - The comma operator, && operator and the || operator shall not be overloaded.
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