Why are deque's pop_front() and pop_back() not noexcept?











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Is there any reason that std::deque's pop_front() and pop_back() are not noexcept in C++11 and higher or was that just forgotten?






c++ c++11 deque c++-standard-library noexcept







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  • How could they be?
    – molbdnilo
    Nov 21 at 12:01















up vote
12
down vote

favorite












Is there any reason that std::deque's pop_front() and pop_back() are not noexcept in C++11 and higher or was that just forgotten?






c++ c++11 deque c++-standard-library noexcept







share|improve this question






















  • How could they be?
    – molbdnilo
    Nov 21 at 12:01













up vote
12
down vote

favorite









up vote
12
down vote

favorite











Is there any reason that std::deque's pop_front() and pop_back() are not noexcept in C++11 and higher or was that just forgotten?






c++ c++11 deque c++-standard-library noexcept







share|improve this question













Is there any reason that std::deque's pop_front() and pop_back() are not noexcept in C++11 and higher or was that just forgotten?






c++ c++11 deque c++-standard-library noexcept




c++ c++11 deque c++-standard-library noexcept






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asked Nov 21 at 11:57









Benjamin Buch

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840716












  • How could they be?
    – molbdnilo
    Nov 21 at 12:01


















  • How could they be?
    – molbdnilo
    Nov 21 at 12:01
















How could they be?
– molbdnilo
Nov 21 at 12:01




How could they be?
– molbdnilo
Nov 21 at 12:01












1 Answer
1






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8
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If I understood correctly, the standard doesn't specify noexcept on functions with a narrow contract (with a precondition which violation leads to UB). N3279 and more recently P0884 are talking about this and about how to decide whether a function should be noexcept or not (or conditionally).



This is the case for std::deque's pop_front and pop_back but also on front and back where there is no call to a destructor. Same for std::vector's pop_back, front and back for example.






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Rémi Galan Alfonso is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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  • 1




    This is correct. The idea was to allow implementations to throw an exception if they detected a contract violation. If these functions were marked as noexcept the program would call std::terminate.
    – Arnaud
    Nov 22 at 16:16











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1 Answer
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active

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1 Answer
1






active

oldest

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active

oldest

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active

oldest

votes








up vote
8
down vote



accepted










If I understood correctly, the standard doesn't specify noexcept on functions with a narrow contract (with a precondition which violation leads to UB). N3279 and more recently P0884 are talking about this and about how to decide whether a function should be noexcept or not (or conditionally).



This is the case for std::deque's pop_front and pop_back but also on front and back where there is no call to a destructor. Same for std::vector's pop_back, front and back for example.






share|improve this answer








New contributor




Rémi Galan Alfonso is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.














  • 1




    This is correct. The idea was to allow implementations to throw an exception if they detected a contract violation. If these functions were marked as noexcept the program would call std::terminate.
    – Arnaud
    Nov 22 at 16:16















up vote
8
down vote



accepted










If I understood correctly, the standard doesn't specify noexcept on functions with a narrow contract (with a precondition which violation leads to UB). N3279 and more recently P0884 are talking about this and about how to decide whether a function should be noexcept or not (or conditionally).



This is the case for std::deque's pop_front and pop_back but also on front and back where there is no call to a destructor. Same for std::vector's pop_back, front and back for example.






share|improve this answer








New contributor




Rémi Galan Alfonso is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.














  • 1




    This is correct. The idea was to allow implementations to throw an exception if they detected a contract violation. If these functions were marked as noexcept the program would call std::terminate.
    – Arnaud
    Nov 22 at 16:16













up vote
8
down vote



accepted







up vote
8
down vote



accepted






If I understood correctly, the standard doesn't specify noexcept on functions with a narrow contract (with a precondition which violation leads to UB). N3279 and more recently P0884 are talking about this and about how to decide whether a function should be noexcept or not (or conditionally).



This is the case for std::deque's pop_front and pop_back but also on front and back where there is no call to a destructor. Same for std::vector's pop_back, front and back for example.






share|improve this answer








New contributor




Rémi Galan Alfonso is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









If I understood correctly, the standard doesn't specify noexcept on functions with a narrow contract (with a precondition which violation leads to UB). N3279 and more recently P0884 are talking about this and about how to decide whether a function should be noexcept or not (or conditionally).



This is the case for std::deque's pop_front and pop_back but also on front and back where there is no call to a destructor. Same for std::vector's pop_back, front and back for example.







share|improve this answer








New contributor




Rémi Galan Alfonso is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









share|improve this answer



share|improve this answer






New contributor




Rémi Galan Alfonso is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









answered Nov 21 at 13:48









Rémi Galan Alfonso

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962




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Rémi Galan Alfonso is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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New contributor





Rémi Galan Alfonso is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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Check out our Code of Conduct.








  • 1




    This is correct. The idea was to allow implementations to throw an exception if they detected a contract violation. If these functions were marked as noexcept the program would call std::terminate.
    – Arnaud
    Nov 22 at 16:16














  • 1




    This is correct. The idea was to allow implementations to throw an exception if they detected a contract violation. If these functions were marked as noexcept the program would call std::terminate.
    – Arnaud
    Nov 22 at 16:16








1




1




This is correct. The idea was to allow implementations to throw an exception if they detected a contract violation. If these functions were marked as noexcept the program would call std::terminate.
– Arnaud
Nov 22 at 16:16




This is correct. The idea was to allow implementations to throw an exception if they detected a contract violation. If these functions were marked as noexcept the program would call std::terminate.
– Arnaud
Nov 22 at 16:16


















 

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