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From: James Curran/MVP (JamesCurran_at_[hidden])
Date: 1999-08-21 03:54:27

From: Reid Sweatman <reids_at_[hidden]>

>class foo
> foo(value_type& T = nValue,bool initialise = false)
>{ if(initialize) Initialize(T); }

Am I missing something? I don't see that working as expected...
Consider the simplified:

class foo
        int n;
        foo(int N = 5,bool initialise = false)
{ if(initialize) n = N; }

Now, Case #1
Written: Foo X;
Effective: foo X(5,false);
Effect: X.n is not initialized.

Case #2
Written: foo X(7)
Effective: foo X(7, false);
Effect: X.n is not initialized.

Case #3
Written: foo X(7, true);
Effective: same
Effect: X.n is initialized to 7.

Case #4
Written: foo X(, true);
Effective: foo X(5, true); // almost....
Effect: X.n would be initialized to 5, if it weren't a syntax error.

        So, it would seem, that the only place where the default for the
second-to-last parameter could be used it, is an error. Furthermore, the
effect of case #2 is counter-intuitive.

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