Question

Assume I have a class foo, and wish to use a std::map to store some boost::shared_ptrs, e.g.:

class foo;  typedef boost::shared_ptr<foo> foo_sp; typeded std::map<int, foo_sp> foo_sp_map;  foo_sp_map m; 

If I add a new foo_sp to the map but the key used already exists, will the existing entry be deleted? For example:

foo_sp_map m;  void func1() {     foo_sp p(new foo);     m[0] = p; }  void func2() {     foo_sp p2(new foo);     m[0] = p2; } 

Will the original pointer (p) be freed when it is replaced by p2? I’m pretty sure it will be, but I thought it was worth asking/sharing.

Answer 1

First off, your question title says boost::auto_ptr, but you actually mean boost::shared_ptr

And yes, the original pointer will be freed (if there are no further shared references to it).