Quote:Original post by Couvillion
There's an STL algorithm you could use, remove_if:

//Make a functor for the removal criterionstruct isTemporary{  bool operator()(ScreenEntityBase* seb)  {     return (seb->GetFlags() & SCREENENTITY_TEMPORARY) > 0;  }};...vector<ScreenEntityBase*>::iterator chopped_end;chopped_end = remove_if(ScreenEntityList.begin(), ScreenEntityList.end(), isTemporary());ScreenEntityList.erase(chopped_end, ScreenEntityList.end());

Untested, of course.

// functor as beforetemplate <typename Container, typename Predicate>void filter(const Container& c, const Predicate& p) {  c.erase(remove_if(c.begin(), c.end(), p), c.end());}filter(ScreenEntityList, isTemporary());

Quote:Original post by Zahlman

// functor as beforetemplate <typename Container, typename Predicate>void filter(const Container& c, const Predicate& p) {  c.erase(remove_if(c.begin(), c.end(), p), c.end());}filter(ScreenEntityList, isTemporary());

? :)

Quote:Original post by Anonymous Poster
"Hello, I am currently using this loop to remove elements from a vector which meet certain criteria, i.e. they are flagged as temporary."

It doesn't sound like a job for vector in my ears...

Quote:Original post by mrmrcoleman
Hello, I am currently using this loop to remove elements from a vector which meet certain criteria, i.e. they are flagged as temporary.

*** Source Snippet Removed ***

This seems to plunge me into am infinite loop. Could somebody please show me the correct way to do this and if possible explain why their's works and why mine doesn't.

Thanks in advance.

Mark Coleman

struct releasing_temporary_entity {    bool operator()( ScreenEntityBase * entity ) const {        if ( (entity->GetFlags() & SCREENENTITY_TEMPORARY) > 0 ) {            entity->Release();            return true;        }        return false;    }};ScreenEntityList.erase    ( std::remove_if        ( ScreenEntityList.begin()        , ScreenEntityList.end()        , releasing_temporary_entity()        )    , ScreenEntityList.end()    );

Quote:Original post by Anonymous Poster
"2) the iterator "it" is invalidated after erasure, along with all iterators after it."

As far as I can see in my cpp-reference, erase() only calls delete for the object that the pointer points to and then clears the pointer.

Quote:From SGI's std::vector documentation:
[5] A vector's iterators are invalidated when its memory is reallocated. Additionally, inserting or deleting an element in the middle of a vector invalidates all iterators that point to elements following the insertion or deletion point. It follows that you can prevent a vector's iterators from being invalidated if you use reserve() to preallocate as much memory as the vector will ever use, and if all insertions and deletions are at the vector's end.

Quote:...and there is an example where you iterate through a vector and delete every object.

Quote:Anyway, vectors should not be used for dynamic purposes in this way...

Quote:Original post by snk_kid

Quote:Original post by Zahlman

// functor as beforetemplate <typename Container, typename Predicate>void filter(const Container& c, const Predicate& p) {  c.erase(remove_if(c.begin(), c.end(), p), c.end());}filter(ScreenEntityList, isTemporary());

? :)

Minor issues, you wanna remove const modifier on the Container type parameter other-wise you can only invoke constant member functions which erase isn't [grin] and for genericity of C++ callable entities you wanna remove the constant reference on the Predicate type aswell,

Quote:throw in some concept checking to prevent types that are not a model of a Sequence from being used and your sorted.