vec.erase(vec.end());合法的？
vec.erase(vec.end()); Legal?
顺序容器可以擦除结尾吗？
标准中说：
a.erase(q)
Requires: For vector and deque, T shall be
MoveAssignable.
Effects: Erases the element pointed to by q
尚不清楚 a.erase(a.end()) 是连续容器的空操作还是 UB。想法？
来自 cplusplus.com："An invalid position or range causes undefined behavior."
如果我们使用 this reference page for erase() :
The iterator pos must be valid and dereferenceable. Thus the end() iterator (which is valid, but is not dereferencable) cannot be used as a value for pos.
所以，不，它是无效的。
§23.2.3 [sequence.reqmts]/p3（强调我的）：
In Tables 100 and 101, X denotes a sequence container class, a
denotes a value of X containing elements of type T, [...], q
denotes a valid dereferenceable const iterator to a.
Table100是序列容器要求table包含a.erase(q).
也就是说，a.erase(a.end())是UB。
顺序容器可以擦除结尾吗？
标准中说：
a.erase(q)
Requires: For vector and deque, T shall be
MoveAssignable.
Effects: Erases the element pointed to by q
尚不清楚 a.erase(a.end()) 是连续容器的空操作还是 UB。想法？
来自 cplusplus.com："An invalid position or range causes undefined behavior."
如果我们使用 this reference page for erase() :
The iterator pos must be valid and dereferenceable. Thus the end() iterator (which is valid, but is not dereferencable) cannot be used as a value for pos.
所以，不，它是无效的。
§23.2.3 [sequence.reqmts]/p3（强调我的）：
In Tables 100 and 101,
Xdenotes a sequence container class, a denotesavalue ofXcontaining elements of typeT, [...],qdenotes a valid dereferenceable const iterator toa.
Table100是序列容器要求table包含a.erase(q).
也就是说，a.erase(a.end())是UB。