Comeau compiler complains (too few arguments for class template "B") at line
***
#include <memory>
template<typena me T, size_t n>
struct A {};
template<typena me T, size_t n>
struct B;
template<typena me T>
struct B<T,2> {};
int main()
{
A<int,2> a;
B<float> b; // ***
}
What am I doing wrong?
--
Tom Tempelaere 4 1967
TT (Tom Tempelaere) wrote in
news:ix******** ************@ph obos.telenet-ops.be: Comeau compiler complains (too few arguments for class template "B") at line ***
#include <memory>
template<typena me T, size_t n> struct A {};
Add a default here if that is what you want.
template<typena me T, size_t n = 3 >
template<typena me T, size_t n> struct B;
template<typena me T> struct B<T,2> {};
int main() { A<int,2> a; B<float> b; // *** }
What am I doing wrong?
Your declaring a default, so you can't use a default.
Either add a sutible default or change line *** to
B< float, 3 > b;
HTH.
Rob.
-- http://www.victim-prime.dsl.pipex.com/
"Rob Williscroft" <rt*@freenet.RE MOVE.co.uk> wrote in message
news:Xn******** *************** ***********@195 .129.110.200... TT (Tom Tempelaere) wrote in news:ix******** ************@ph obos.telenet-ops.be:
Comeau compiler complains (too few arguments for class template "B") at line ***
#include <memory>
template<typena me T, size_t n> struct A {};
Add a default here if that is what you want.
template<typena me T, size_t n = 3 >
That is _not_ what I want to do. template<typena me T, size_t n> struct B;
template<typena me T> struct B<T,2> {};
int main() { A<int,2> a; B<float> b; // *** }
What am I doing wrong?
Your declaring a default, so you can't use a default.
I am not declaring a default, I'm partially specializing a template class.
That has nothing to do with defaults!
Either add a sutible default or change line *** to
B< float, 3 > b;
That would make partial specialization totally unusable!
Do you actually know what partial specialization of a template class is?
HTH.
Rob.
Tom.
TT (Tom Tempelaere) wrote in
news:_j******** ************@ph obos.telenet-ops.be: "Rob Williscroft" <rt*@freenet.RE MOVE.co.uk> wrote in message news:Xn******** *************** ***********@195 .129.110.200... TT (Tom Tempelaere) wrote in news:ix******** ************@ph obos.telenet-ops.be:
[snip] Add a default here if that is what you want.
template<typena me T, size_t n = 3 > That is _not_ what I want to do.
Actually when you combine the default with the specialization, it
probably is, but you didn't say what you wanted to do.
> template<typena me T, size_t n> > struct B; > > template<typena me T> > struct B<T,2> {}; > > int main() > { > A<int,2> a; > B<float> b; // *** > } > > What am I doing wrong? Your declaring a default, so you can't use a default.
Whoops missed a *not* in the above, It should have been:
Your not declaring a default, so you can't use a default.
I am not declaring a default, I'm partially specializing a template class. That has nothing to do with defaults!
Yes you are, but then you try to use the class as if you had
given it a default for its second paramiter. Either add a sutible default or change line *** to
B< float, 3 > b; That would make partial specialization totally unusable!
You seem to be confused about what specialization does.
There can be only one class or class-template named B, if its
a class-template say B< typename, size_t > then it takes 2
arguments, specialization *isn't* overloading.
From your code above:
B< int, 1 > b1; // will instantiate the the unspecialized template.
B< int, 2 > b2; // will instantiate the specialization. Do you actually know what partial specialization of a template class is?
:) Yes *I* do. HTH.
Rob.
-- http://www.victim-prime.dsl.pipex.com/
"Rob Williscroft" <rt*@freenet.RE MOVE.co.uk> wrote in message
news:Xn******** *************** ***********@195 .129.110.205... TT (Tom Tempelaere) wrote in news:_j******** ************@ph obos.telenet-ops.be:
"Rob Williscroft" <rt*@freenet.RE MOVE.co.uk> wrote in message news:Xn******** *************** ***********@195 .129.110.200... TT (Tom Tempelaere) wrote in news:ix******** ************@ph obos.telenet-ops.be:
[snip] Add a default here if that is what you want.
template<typena me T, size_t n = 3 >
That is _not_ what I want to do.
Actually when you combine the default with the specialization, it probably is, but you didn't say what you wanted to do.
> template<typena me T, size_t n> > struct B; > > template<typena me T> > struct B<T,2> {}; > > int main() > { > A<int,2> a; > B<float> b; // *** > } > > What am I doing wrong?
Your declaring a default, so you can't use a default.
Whoops missed a *not* in the above, It should have been:
Your not declaring a default, so you can't use a default.
I am not declaring a default, I'm partially specializing a template class. That has nothing to do with defaults!
Yes you are, but then you try to use the class as if you had given it a default for its second paramiter.
Either add a sutible default or change line *** to
B< float, 3 > b;
That would make partial specialization totally unusable!
You seem to be confused about what specialization does.
There can be only one class or class-template named B, if its a class-template say B< typename, size_t > then it takes 2 arguments, specialization *isn't* overloading.
From your code above:
B< int, 1 > b1; // will instantiate the the unspecialized template.
B< int, 2 > b2; // will instantiate the specialization.
Do you actually know what partial specialization of a template class is?
:) Yes *I* do.
:-)) I think I got it all screwed up. You are correct.
I'm sorry for questioning you.
Thanks,
Tom. HTH.
Rob. -- http://www.victim-prime.dsl.pipex.com/ This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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