Re: problem with default argument with template args
On 17 Nov., 21:05, Andrew <marlow.and...@googlemail.com> wrote:
I cannot see what is wrong with the code below:
template<class A, class B>
class Arg {
public:
Arg() {};
};
template<class A, class B>
class User {
public:
User(const char* username,
Arg<A,B> arg = Arg<A,B>(),
bool flag = false)
{
};
};
gcc fails to compile it. The error output is:
ex2.cpp:12: error: expected `,' or `...' before '>' token
ex2.cpp:12: error: missing `>' to terminate the template argument list
ex2.cpp:12: error: wrong number of template arguments (1, should be 2)
ex2.cpp:3: error: provided for `template<class A, class B> class Arg'
Taking out the defaulting of the template argument makes the problem
go away.
This example, is a cutdown from some legacy code I am looking it. I am
trying to get it to compile with gcc. It compiles with Visual Studio
2005, but then lots of illegal C++ is let through with *that*
compiler.
I see neither a problem for theoretical reasons
nor from practical tests with a most recent gcc
4.4.1. Either you are using an older/buggy compiler
or the actual reason for the compiler error
has been eliminated during code simplification.
In my test I instantiated the User template via
User<int, bool> u("");
HTH & Greetings from Bremen,
Daniel Kr?gler
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