Webb3 dec. 2014 · shared_ptr already has a well defined empty state. Wrapping the whole thing inside optional seems redundant. There is no indication in the Obj-C/Java interface telling a user where passing nil or null is OK or not, contrary to the C++ signature. The difference only manifests itself in the form of a runtime error if used incorrectly. Webb7 feb. 2024 · A shared pointer needs two raw pointers. A set of shared pointers which have the same managed object need a control unit. Therefore, the memory that a shared …

shared_ptr - C++ Reference - cplusplus.com

Webb29 nov. 2016 · shared_ptr provides a specific operator for bool conversion std::shared_ptr::operator bool. Test if not set: if (!p) Test if set: if (p) You can be very explicit about your intent with: if (static_cast (p)) Share Improve this answer Follow answered Mar 25, 2024 at 12:43 Antonio 19.1k 12 96 195 WebbConstruct shared_ptr Constructs a shared_ptr object, depending on the signature used: default constructor (1), and (2) The object is empty (owns no pointer, use count of zero). … hills lighting and bar stools

shared_ptr class Microsoft Learn

WebbA shared_ptr that does not own any pointer is called an empty shared_ptr. A shared_ptr that points to no object is called a null shared_ptr and shall not be dereferenced . Notice … sp4; We can set it later sp4 = sp3; Operations Let’s consider class A again struct A{ int M; A(int m):M(m) {} }; A shared pointer supports usual pointer dereferencing (*sp1).M = 1; sp1-> M = 2; The shared pointer is, in fact, a class which has a raw pointer pointing to the managed object. Webb7 aug. 2010 · 2 Answers Sorted by: 8 Yes, the code you have above is correct. shared_ptr can be implicitly converted to a bool to check for null-ness. The problem you have is your returnAnIterator () function is returning an invalid iterator. smart glasses as computer monitor