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error "missing 'typename' prior to dependent type name 'vector<T, A>::iterator'"

DragonOsman (715)
It's giving me the error mentioned in the title on this code in the custom vector from the book PPP2:
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template<typename T, typename A>
vector<T, A>::iterator vector<T, A>::insert(vector<T, A>::iterator p, const T &val)
{
	int index = p - begin();
	if (size() == capacity())
	{
		reserve(size() == 0 ? 8 : 2 * size());		// make sure we have space
	}

	// first copy last element into uninitialized space
	alloc.construct(elem + sz, *back());

	++sz;
	iterator pp = begin() + index;		// the place to put val
	for (auto pos = end() - 1; pos != pp; --pos)
	{
		*pos = *(pos - 1);		// copy elements one position to the right
	}
	*(begin() + index) = val;		// "insert" val
	return pp;
}

template<typename T, typename A>
vector<T, A>::iterator vector<T, A>::erase(vector<T, A>::iterator p)
{
	if (p == end())
	{
		return p;
	}
	for (auto pos = p + 1; pos != end(); ++pos)
	{
		*(pos - 1) = *pos;		// copyy element "one position to the left"
	}
	alloc.destroy(&*(end() - 1));		// destroy surplus copy of last element
	--sz;
	return p;
}


I've clearly done what it's asking, so why is it saying that?

If anyone wants to look at it in the context of the full header file (it's a header file I wrote), please let me know and I'll show it.
DragonOsman (715)
Solved by doing this:
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template<typename T, typename A>
typename vector<T, A>::iterator vector<T, A>::insert(vector<T, A>::iterator p, const T &val)
for insert() and erase().

So is it because the compiler needs to tell for sure that it's a typename alias for a vector::T* and not a greater-than or less-than comparison? Is that the reason for this?

Anyway, yeah, thanks.
gunnerfunner (2127)
DragonOsman (715)
Has the "Down with the typename!" proposal already been accepted in C++17? Or is it still just a proposal?
mbozzi (3911)
No - and it won't be - we'll have to wait. C++17 is feature-complete and has been for a few months.

FYI, the paper is numbered p0634r1.
Last edited on
DragonOsman (715)
Ah, so the proposal was made after the standard became feature-complete (or maybe just at such a time that it couldn't make it into the standard in time)?

Anyway, the initial problem has already been solved, so I'll mark it as such.
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