[Boost-users] Shared_ptr and constness

From: cyril.godart_at_[hidden]
Date: 2003-12-12 06:28:51

Hi,

Just out of curiosity. I am increasingly using the smart_ptr and more
specifically the shared_ptr but I came to realize that actually it rather
violently breaches the constness rules. The example below is
one of the many things you can do with a shared pointer that is forbidden
with a naked pointer. As the shared_ptr penetrates even further in my
code I come to realize that what I am gaining on the comfort side
I loose on the safety. Clearly, that's my call but I was curious to know
if it is a known fact that it is impossible to enforce constness rules.

Cyril Godart
Quantitative Analyst
BNP Paribas.

struct A
{
      int bar;
};
typedef boost::shared_ptr<A> A_ptr_t;
void foo(const A_ptr_t& a)
{
      a->bar++;//semantically this should not be possible.
}
int main(int argc, char* argv[])
{
      A_ptr_t a(new A);
      a->bar = 1;
      foo(a);

      return 0;
}

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