Stefan Kuhlins wrote:
>
> Some container classes declare the member function
> assign as member template like this:
>
>   template <class T, class Allocator = allocator<T> >
>   class vector {
>   public:
>     template <class Size, class U>
>     void assign(Size n, const U& u = U());
>     // ...
>   };
>
> What should a compiler generate for a call like this?
>
>   vector<int> v;
>   v.assign(3);

Nothing. The type can't be deduced.

> What's the right way?

It's the standard conforming one:

void assign(Size n, const T& u);

That is, not template, no stupid default argument.

All these silly defaults have been droped, except
for string.

--

Valentin Bonnard                mailto:bonnardv@pratique.fr
info about C++/a propos du C++: http://www.pratique.fr/~bonnardv/
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Some container classes declare the member function
assign as member template like this:

  template <class T, class Allocator = allocator<T> >
  class vector {
  public:
    template <class Size, class U>
    void assign(Size n, const U& u = U());
    // ...
  };

What should a compiler generate for a call like this?

  vector<int> v;
  v.assign(3);

It's not clear what type U should be!
Maybe this could work:

  v.template assign<int, int>(3);
  // see WP 14.2 (4) [temp.names]

A better solution might be:

  template <class Size, class U>
  void assign(Size n, const U& u = T());
                                   ^^^
I tested this with KCC, but it doesn't compile.

What's the right way?

- Stefan
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