Re: [boost] painless currying

Subject: Re: [boost] painless currying
From: Larry Evans (cppljevans_at_[hidden])
Date: 2011-09-03 12:21:24

On 09/03/11 11:12, Eric Niebler wrote:
> On 9/3/2011 10:48 AM, Larry Evans wrote:
>> when passed arguments that cannot
>> possibly be valid, the arguments just keep accummulating
>> in the curryable<F,Args...>::argI.  
> 
> Correct.
> 
>> It would be helpful
>> if some diagnostic were issued in case too many arguments
>> are supplied.
> 
> I agree it would be helpful, but I don't think that's possible. Without
> true introspection, there is no way to know a priori what the max arity
> of the bound function is, hence no way to know when we've accumulated
> more arguments than are valid. It just keeps collecting arguments in a
> vain attempt to satisfy the can_be_called predicated.
> 
OK, so *now* I see a good use-case for David Abraham's point:

http://lists.boost.org/Archives/boost/2011/08/185096.php

about using () to cause evaluation.  The user would then know if invalid
arguments were supplied.