[boost] Re: compressed_pair requirements?

From: Howard Hinnant (hinnant_at_[hidden])
Date: 2005-05-27 16:52:08

On May 27, 2005, at 4:45 PM, Peter Dimov wrote:

> But what for? If you want to print random values to stdout, it's 
> easier to just use std::rand.

The quality of my generator is better than rand. :-)

> Didn't we already go over this some years ago? The result was a 
> proposed vector constructor that left its members uninitialized and 
> then called a user-supplied function that initialized them.

<nod> Yeah, we really need to get that one in there.

> And in any event, compressed_pair leaving its members uninitialized 
> when std::pair doesn't is a pretty elegant way to sneak bugs into 
> innocent people's code when they aren't looking. An <evil laugh> would 
> be entirely appropriate here as well. ;-)

True, but fixing std::pair to do the right thing would break backwards 
compatibility. :-)

On May 27, 2005, at 4:48 PM, JOAQUIN LOPEZ MU?Z wrote:

> IMHO, std::pair default ctor should be defined as
>
> pair():first(),second(){}

We've got you covered on that one:

http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#265

-Howard