[boost] Re: shared_ptr question (with respect to thread safety)

From: David B. Held (dheld_at_[hidden])
Date: 2003-02-06 16:35:10

"Trey Jackson" <tjackson_at_[hidden]> wrote in message
news:qkxy94t2kfb.fsf_at_dlxc0015.pdx.intel.com...
> [...]
> I was unable to get that to compile.
> Linux gcc 3.2.1, or HP aCC: HP ANSI C++ B3910B X.03.32
>
> The linux error gave me a syntax error before the '{' token on the lines
> declaring 'insertCode' in both SubstituteHello and SubstituteGoodbye.

That's correct.

> ,----------------
> | #include <iostream>
> |
> | using std::cout; using std::endl;
> |
> | template<class ToBeSubstituted>
> | struct userClass {
> |    void function() {
> |      // code is inserted here, not a function call to a member of
> |      ToBeSubstituted::insertCode();
> |   }
> | };
> |
> | struct SubstituteHello {
> |   typedef void fn();
> |
> |   static fn insertCode {
> |     cout << "hello world" << endl;
> |   }
> | };

You can use a typedef to declare a function, but not to define one.
This code should actually be:

static void insertCode() { ...

> | struct SubstituteGoodbye {
> |   typedef void fn();
> |
> |   static fn insertCode {
> |     cout << "goodbye world" << endl;
> |   }
> | };

And here.

> [...]
> This compiles, runs with undesired behavior;
> ,----------------
> | struct SubstituteHello {
> |   typedef void fn();
> |
> |   static void insertCode()
> |   {
> |     dummy d;
> |     cout << "Hello World" << endl;
> |   }

That's pretty much how you have to do it.

> | //    typedef void fn();
> | //    static fn insertCode {
> | //      cout << "hello world" << endl;
> | //    }
> | };
> `----------------
> [...]

Dave