'std::vector<T>::iterator it;' doesn't compile
I've got this function开发者_开发百科:
template<typename T>
void Inventory::insertItem(std::vector<T>& v, const T& x)
{
std::vector<T>::iterator it; // doesn't compile
for(it=v.begin(); it<v.end(); ++it)
{
if(x <= *it) // if the insertee is alphabetically less than this index
{
v.insert(it, x);
}
}
}
and g++ gives these errors:
src/Item.hpp: In member function ‘void
yarl::item::Inventory::insertItem(std::vector<T, std::allocator<_CharT> >&, const T&)’:
src/Item.hpp:186: error: expected ‘;’ before ‘it’
src/Item.hpp:187: error: ‘it’ was not declared in this scope
it must be something simple, but after ten minutes of staring at it I can't find anything wrong. Anyone else see it?
Try this instead:
typename std::vector<T>::iterator it;
Here's a page that describes how to use typename and why it's necessary here.
What you are doing is inefficient. Use a binary search instead:
#include <algorithm>
template <typename T>
void insertItem(std::vector<T>& v, const T& x)
{
v.insert(std::upper_bound(v.begin(), v.end(), x), x);
}
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