Re: mutex_traits<>

From: bill_kempf (williamkempf_at_[hidden])
Date: 2002-01-31 13:49:31

--- In boost_at_y..., "David Abrahams" <david.abrahams_at_r...> wrote:
> 
> ----- Original Message -----
> From: "bill_kempf" <williamkempf_at_h...>
> 
> > What alternative design do you propose?
> 
> How about the free functions proposed by Jeremy?

Again, the free function approach doesn't discourage usage 
by "newbies".  I've seen many MT libraries that expose lock/unlock on 
the mutex class's public interface (which is equivalent to free 
functions) as well as providing the Scoped Lock classes for "safer" 
usage.  Despite documentation warning of the issues most "newbies" 
invariably call lock/unlock directly instead of using the Scoped 
Lock, and the result is usually buggy programs that seem to run 
during testing but deadlock when software is released.  Maybe I'm 
trying to hard, but I want to prevent this newbie mistake while not 
preventing the experts from easily extending the library in ways that 
scoped locking causes problems.

> BTW, I note that traits classes normally don't have functions
> (numeric_limits<>::min()/max() are nasty outliers), so that also 
grates on
> me a bit as un-idiomatic?

std::char_traits<> has 14 static functions.  Is it really un-
idiomatic?

Bill Kempf