自动推断bind1st（mem_fun（＆my_class :: f），this）的类型？

Question

I would like to pass the bind1st(mem_fun(&my_class::f), this) functor to for_each . Unfortunately it is very difficult to read so I would like to give it a more readible name like this:

(the type I am looking for) meaningful_name = bind1st(mem_fun(&my_class::f), this);

for_each(v.begin(), v.end(), meaningful_name);

Is there a simple way to deduce the type of the functor? (I know mem_fun saves us a lot of pain exactly for this reason.)

Answer 1

This depends on the argument and return types of my_class:f. If the function is

T my_class::f(A arg)

then you need

binder1st<mem_fun1_t<T,my_class,A> > meaningful_name = bind1st(mem_fun(&my_class::f), this);

This kind of thing will be nicer with C++0x:

auto meaningful_name = bind1st(mem_fun(&my_class::f), this);

Answer 2

No there is no simple way. The type name will be rather long and even more unreadable. And if you use boost, you don't need to use BOOST_AUTO , because you can just use boost::bind and have it readable, without a need for a local.

for_each(v.begin(), v.end(), boost::bind(&my_class::f, this));