__VA_ARGS__

[Russell Shaw]

Hi,

I have a variadic macro:

#define throw(msg, ...) excep_throw(msg, __VA_ARGS__)
If i do: throw("Error", 0), it compiles ok.

If i do: throw("Error"), i get an error:

error: parse error before ')' token
I think it's because without the last parameter, the function is
called as: except_throw("Error", ). How do i get rid of this trailing
comma problem?

I'm using gcc-3.4.4.
void excep_throw(char *msg, ...)
{
...
}

[Russell Shaw]

Russell Shaw wrote:

Hi,

I have a variadic macro:

#define throw(msg, ...) excep_throw(msg, __VA_ARGS__)
If i do: throw("Error", 0), it compiles ok.

If i do: throw("Error"), i get an error:

error: parse error before ')' token
I think it's because without the last parameter, the function is
called as: except_throw("Error", ). How do i get rid of this trailing
comma problem?

I'm using gcc-3.4.4.
void excep_throw(char *msg, ...)
{
...
}

Disregard, i figured it out. Always have one mandatory parameter
withing the va-args.

[William Ahern]

Russell Shaw <rjshawN_o@s_pam.netspace.net.au> wrote:

Hi, ? I have a variadic macro:

#define throw(msg, ...) excep_throw(msg, __VA_ARGS__)
If i do: throw("Error", 0), it compiles ok.

If i do: throw("Error"), i get an error:

error: parse error before ')' token
I think it's because without the last parameter, the function is
called as: except_throw("Error", ). How do i get rid of this trailing
comma problem?

#define throw(...) excep_throw(__VA_ARGS__)

[James Hess]

Russell Shaw wrote:

Hi,

I have a variadic macro:

#define throw(msg, ...) excep_throw(msg, __VA_ARGS__)

Try

#define throw(msg, ...) excep_throw(msg, ##__VA_ARGS__)

-J. Hess

[Ben Pfaff]

"James Hess" <my*****@gmail.com> writes:

Russell Shaw wrote:

I have a variadic macro:

#define throw(msg, ...) excep_throw(msg, __VA_ARGS__)

Try

#define throw(msg, ...) excep_throw(msg, ##__VA_ARGS__)

That solution is specific to GCC.
--
"...deficient support can be a virtue.
It keeps the amateurs off."
--Bjarne Stroustrup