Re: [Boost-users] [Bind] Unexpected behavior when binding const char* to function

Hello, Igor R writes:

...

function f = boost::bind(echo, s.c_str());

The expression x.c_str() returns a pointer that becomes invalid as soon as any non-const member function of std::string is called for x.

I know reason behind. But use is right to think "I've bind >>abc<<. Binder should store it and use on f() invocation". In real code the situation could be even worse - if f can be stored for future use and invoked when s has already been destroyed. Passing string instead of const char* behaves exactly how expected void echo2(const string& s) { cout << s << '\n'; } int main() { string s2 = "abc"; function f2 = boost::bind(echo2, s2); s2 = "xyz"; f(); } My point is that difference between binding to echo and echo2 (string vs. const char*) should not lead do different behavior. Otherwise user has to be very careful on signature of bind'ed function. Binding to function that accepts const char* leads to very strange results. It resembles me infamous scanf().

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