I try to remove objects from a vector using vector::erase and std::remove_if. I have an external namespace which does the selection ala:
template<unsigned int value, someType collection>
bool Namespace::isValid(const Foo* object){
do something
}
Now I have a vector which contains some element which I want to filter if the are valid. In order to do so I do:
std::vector<foo*> myVector;
//fill it
myVector.erase( std::remove_if(myVector.begin(), myVector.end(), Namespace::isValid<myValue, myCollectionType>), myVector.end());
Now this works fine and removes all valid candidates, but actually I want to keep and remove all other. Hence, I need to negate the predicate. Is there any way to do so? Unfortunately, C++11 is not currently supported in this context.
Thanks
Use the std::not1
adapter to negate the value returned by your isValid
function. Note that std::not1
expects a function object (C++ calls this a "functor"), so if you have a plain function in a name space you will also need std::ptr_fun
to create a function object out of your function.
So,
myVector.erase( std::remove_if( myVector.begin(),
myVector.end(),
Namespace::isValid<myValue, myCollectionType> ),
myVector.end() );
becomes
myVector.erase( std::remove_if( myVector.begin(),
myVector.end(),
std::not1( std::ptr_fun( Namespace::isValid<myValue, myCollectionType> ) ) ),
myVector.end() );
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