Re: Policy-based vector? [was: Submission: Fixed-Capacity STL Containers Library]

From: mfdylan (dylan_at_[hidden])
Date: 2002-02-06 22:03:08

--- In boost_at_y..., "Noah Stein" <noah_at_v...> wrote:
> 
> 
> I like the idea of being able to accept default values anywhere one 
is
> present.  I think it would be preferable, though, to have an 
explicit
> declaration of intent to use the default value instead of merely 
omitting
> the argument.  Since it is already a keyword, I would suggest using
> "default" to specify an argument of default value.
> 
Perhaps both should be permitted.  After all the only current way to 
specify a default argument is to omit it, so it would seem reasonable 
to allow omission for arguments other than the last.
The idea of named parameters is more interesting, but it's not 
obvious how to do this for function calls, where parameter names can 
be omitted, the operator = couldn't be used, and where parameter 
names would be somehow injected into the callee's namespace:

int foo(int a, int b = 2, int c = 3);

void bar()
{
 int a, b, c, d;
 ...
 d = foo(a := a, c := 4); 
}

But I guess other languages have this problem too...

Dylan