STL: Searching with binders and predicates

M

Maitre Bart

In test.cpp, I have a class CRunner that holds the runner's name (string)
and the runner's order (int).

To get the name, the method to use is GetName().
To get the order, the method to use is GetOrder().

I made a vector<CRunner> (RunnerVec). I initialized both name and order to
all entries. I set all order to 3 except the one before the last which has
order = 5.

My goal is to formulate a statement using find_if, binders and any std
predicate (such as not_equal_to). I coded the following in order to get the
iterator on the runner that has an order different than 3:

vector<CRunner>::iterator it = find_if(RunnerVec.begin(), RunnerVec.end(),
....

where the "..." stand for the following attempts:

1: bind2nd(mem_fun_ref(&CRunner::GetOrder),
bind2nd(not_equal_to<int>(),3)));

Despite my understanding, it does not compile:

....\functional(175): error C2039: 'first_argument_type': is not a member of
'mem_fun_ref_t<int,CRunner>'
....\test.cpp(228): see reference to class template instantiation
'binder2nd<mem_fun_ref_t<int,CRunner>>' being compiled
....\functional(175): error C2065: 'first_argument_type': undeclared
identifier
....\test.cpp(228): see reference to class template instantiation
'binder2nd<mem_fun_ref_t<int,CRunner>>' being compiled
....\functional(176): fatal error C1903: unable to recover from previous
error(s); stopping compilation
Command line warning D4028 : minimal rebuild failure, reverting to normal
build

2: mem_fun_ref(&CRunner::GetOrder));
3: bind2nd(not_equal_to<CRunner>(),RunnerVec[0]));

Individually, they compile, although it does not give what I am expecting
(of course!).

4 and up:

Back to 1, I tried different argument positions and interchanging
bind1st/bind2nd without success (gives the similar errors).

Is it possible to combine both binders i.e. get the right code so 1)
GetOrder() is called upon each CRunner of the vector and 2) be compared to
3, without using home-made predicate?

Thanks for you help.
 

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question

Members online

No members online now.

Forum statistics

Threads
473,764
Messages
2,569,565
Members
45,041
Latest member
RomeoFarnh

Latest Threads

Top