Re: [Boost-users] [lambda] Using lambda expressions with STL function adaptors

From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2008-07-19 16:24:00

AMDG

Robert Jones wrote:
> Yes, the logic of that is undeniable, so I'm going to backtrack a bit as
> somewhere my understanding has gone astray.
>
> What I think I know:
>
> * That boost::lambda::bind( ) creates 'conformant' functors.

It depends on what you mean by conformant.  Algorithms like
for_each do not require these typedefs.  Adapters like not1
do.  If you need to adapt an arbitrary function object,
you're safer using !boost::bind<bool>(pred) instead of
std::not1.  This will also work with function pointers. (Which
std::not1 doesn't handle)

> What I've assumed from what I know:
>
> * That 'conformant' includes defining the argument_type typedef

Again, it depends on what you mean by conformant.

> * That what is true for bind is also true lambda expressions.

Meaning lambda::bind?  The result of lambda::bind /is a/ lambda expression.

In Christ,
Steven Watanabe