libogre-1.9-dev 1.9.0+dfsg1-4 / usr / include / OGRE / OgreSmallVector.h

//===- llvm/ADT/SmallVector.h - 'Normally small' vectors --------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
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// This file is distributed under the University of Illinois Open Source
// License.
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// Open Source License
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// Copyright (c) 2003-2010 University of Illinois at Urbana-Champaign.
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// Developed by:
//
// LLVM Team
//
// University of Illinois at Urbana-Champaign
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// this software and associated documentation files (the "Software"), to deal with
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
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//===----------------------------------------------------------------------===//
//
// This file defines the SmallVector class.
//
//===----------------------------------------------------------------------===//

#ifndef __SmallVector_H
#define __SmallVector_H

#include <algorithm>
#include <cassert>
#include <cstddef>
#include <cstdlib>
#include <cstring>
#include <iterator>
#include <memory>

#ifdef _MSC_VER
namespace std {
#if _MSC_VER <= 1310
	// Work around flawed VC++ implementation of std::uninitialized_copy.  Define
	// additional overloads so that elements with pointer types are recognized as
	// scalars and not objects, causing bizarre type conversion errors.
	template<class T1, class T2>
	inline _Scalar_ptr_iterator_tag _Ptr_cat(T1 **, T2 **) {
		_Scalar_ptr_iterator_tag _Cat;
		return _Cat;
	}
	
	template<class T1, class T2>
	inline _Scalar_ptr_iterator_tag _Ptr_cat(T1* const *, T2 **) {
		_Scalar_ptr_iterator_tag _Cat;
		return _Cat;
	}
#else
	// FIXME: It is not clear if the problem is fixed in VS 2005.  What is clear
	// is that the above hack won't work if it wasn't fixed.
#endif
}
#endif

namespace Ogre {
	
    // some type traits
	template <typename T>	struct isPodLike { static const bool value = false; };
	
	template <>				struct isPodLike<bool>				{ static const bool value = true; };
	template <>				struct isPodLike<char>				{ static const bool value = true; };
	template <>				struct isPodLike<signed char>		{ static const bool value = true; };
	template <>				struct isPodLike<unsigned char>		{ static const bool value = true; };
	template <>				struct isPodLike<int>				{ static const bool value = true; };
	template <>				struct isPodLike<unsigned>			{ static const bool value = true; };
	template <>				struct isPodLike<short>				{ static const bool value = true; };
	template <>				struct isPodLike<unsigned short>	{ static const bool value = true; };
	template <>				struct isPodLike<long>				{ static const bool value = true; };
	template <>				struct isPodLike<unsigned long>		{ static const bool value = true; };
	template <>				struct isPodLike<float>				{ static const bool value = true; };
	template <>				struct isPodLike<double>			{ static const bool value = true; };
	template <typename T>	struct isPodLike<T*>				{ static const bool value = true; };
	
	template<typename T, typename U>
	struct isPodLike<std::pair<T, U> > { static const bool value = isPodLike<T>::value & isPodLike<U>::value; };

	/// SmallVectorBase - This is all the non-templated stuff common to all
	/// SmallVectors.
	class SmallVectorBase {
	protected:
		void *BeginX, *EndX, *CapacityX;
		
		// Allocate raw space for N elements of type T.  If T has a ctor or dtor, we
		// don't want it to be automatically run, so we need to represent the space as
		// something else.  An array of char would work great, but might not be
  // aligned sufficiently.  Instead we use some number of union instances for
  // the space, which guarantee maximal alignment.
  union U {
				double D;
				long double LD;
				long long L;
				void *P;
		} FirstEl;
		// Space after 'FirstEl' is clobbered, do not add any instance vars after it.
		
	protected:
		SmallVectorBase(size_t Size)
		: BeginX(&FirstEl), EndX(&FirstEl), CapacityX((char*)&FirstEl+Size) {}
		
		/// isSmall - Return true if this is a smallvector which has not had dynamic
		/// memory allocated for it.
		bool isSmall() const {
			return BeginX == static_cast<const void*>(&FirstEl);
		}
		
		/// size_in_bytes - This returns size()*sizeof(T).
		size_t size_in_bytes() const {
			return size_t((char*)EndX - (char*)BeginX);
		}
		
		/// capacity_in_bytes - This returns capacity()*sizeof(T).
		size_t capacity_in_bytes() const {
			return size_t((char*)CapacityX - (char*)BeginX);
		}
		
		/// grow_pod - This is an implementation of the grow() method which only works
  /// on POD-like data types and is out of line to reduce code duplication.
		void grow_pod(size_t MinSizeInBytes, size_t TSize);
		
	public:
		bool empty() const { return BeginX == EndX; }
	};
	
	
	template <typename T>
	class SmallVectorTemplateCommon : public SmallVectorBase {
	protected:
		void setEnd(T *P) { this->EndX = P; }
	public:
		SmallVectorTemplateCommon(size_t Size) : SmallVectorBase(Size) {}
		
		typedef size_t size_type;
		typedef ptrdiff_t difference_type;
		typedef T value_type;
		typedef T *iterator;
		typedef const T *const_iterator;
		
		typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
		typedef std::reverse_iterator<iterator> reverse_iterator;
		
		typedef T &reference;
		typedef const T &const_reference;
		typedef T *pointer;
		typedef const T *const_pointer;
		
		// forward iterator creation methods.
		iterator begin() { return (iterator)this->BeginX; }
		const_iterator begin() const { return (const_iterator)this->BeginX; }
		iterator end() { return (iterator)this->EndX; }
		const_iterator end() const { return (const_iterator)this->EndX; }
	protected:
		iterator capacity_ptr() { return (iterator)this->CapacityX; }
		const_iterator capacity_ptr() const { return (const_iterator)this->CapacityX;}
	public:
		
		// reverse iterator creation methods.
		reverse_iterator rbegin()            { return reverse_iterator(end()); }
		const_reverse_iterator rbegin() const{ return const_reverse_iterator(end()); }
		reverse_iterator rend()              { return reverse_iterator(begin()); }
		const_reverse_iterator rend() const { return const_reverse_iterator(begin());}
		
		size_type size() const { return end()-begin(); }
		size_type max_size() const { return size_type(-1) / sizeof(T); }
		
		/// capacity - Return the total number of elements in the currently allocated
		/// buffer.
		size_t capacity() const { return capacity_ptr() - begin(); }
		
		/// data - Return a pointer to the vector's buffer, even if empty().
		pointer data() { return pointer(begin()); }
		/// data - Return a pointer to the vector's buffer, even if empty().
		const_pointer data() const { return const_pointer(begin()); }
		
		reference operator[](unsigned idx) {
			assert(begin() + idx < end());
			return begin()[idx];
		}
		const_reference operator[](unsigned idx) const {
			assert(begin() + idx < end());
			return begin()[idx];
		}
		
		reference front() {
			return begin()[0];
		}
		const_reference front() const {
			return begin()[0];
		}
		
		reference back() {
			return end()[-1];
		}
		const_reference back() const {
			return end()[-1];
		}
	};
	
	/// SmallVectorTemplateBase<isPodLike = false> - This is where we put method
	/// implementations that are designed to work with non-POD-like T's.
	template <typename T, bool isPodLike>
	class SmallVectorTemplateBase : public SmallVectorTemplateCommon<T> {
	public:
		SmallVectorTemplateBase(size_t Size) : SmallVectorTemplateCommon<T>(Size) {}
		
		static void destroy_range(T *S, T *E) {
			while (S != E) {
				--E;
				E->~T();
			}
		}
		
		/// uninitialized_copy - Copy the range [I, E) onto the uninitialized memory
		/// starting with "Dest", constructing elements into it as needed.
		template<typename It1, typename It2>
		static void uninitialized_copy(It1 I, It1 E, It2 Dest) {
			std::uninitialized_copy(I, E, Dest);
		}
		
		/// grow - double the size of the allocated memory, guaranteeing space for at
		/// least one more element or MinSize if specified.
		void grow(size_t MinSize = 0);
	};
	
	// Define this out-of-line to dissuade the C++ compiler from inlining it.
	template <typename T, bool isPodLike>
	void SmallVectorTemplateBase<T, isPodLike>::grow(size_t MinSize) {
		size_t CurCapacity = this->capacity();
		size_t CurSize = this->size();
  size_t NewCapacity = 2*CurCapacity + 1; // Always grow, even from zero.
		if (NewCapacity < MinSize)
			NewCapacity = MinSize;
		T *NewElts = static_cast<T*>(malloc(NewCapacity*sizeof(T)));
		
		// Copy the elements over.
		this->uninitialized_copy(this->begin(), this->end(), NewElts);
		
		// Destroy the original elements.
		destroy_range(this->begin(), this->end());
		
		// If this wasn't grown from the inline copy, deallocate the old space.
		if (!this->isSmall())
			free(this->begin());
		
		this->setEnd(NewElts+CurSize);
		this->BeginX = NewElts;
		this->CapacityX = this->begin()+NewCapacity;
	}
	
	
	/// SmallVectorTemplateBase<isPodLike = true> - This is where we put method
	/// implementations that are designed to work with POD-like T's.
	template <typename T>
	class SmallVectorTemplateBase<T, true> : public SmallVectorTemplateCommon<T> {
	public:
		SmallVectorTemplateBase(size_t Size) : SmallVectorTemplateCommon<T>(Size) {}
		
		// No need to do a destroy loop for POD's.
		static void destroy_range(T *, T *) {}
		
		/// uninitialized_copy - Copy the range [I, E) onto the uninitialized memory
		/// starting with "Dest", constructing elements into it as needed.
		template<typename It1, typename It2>
		static void uninitialized_copy(It1 I, It1 E, It2 Dest) {
			// Arbitrary iterator types; just use the basic implementation.
			std::uninitialized_copy(I, E, Dest);
		}
		
		/// uninitialized_copy - Copy the range [I, E) onto the uninitialized memory
		/// starting with "Dest", constructing elements into it as needed.
		template<typename T1, typename T2>
		static void uninitialized_copy(T1 *I, T1 *E, T2 *Dest) {
			// Use memcpy for PODs iterated by pointers (which includes SmallVector
			// iterators): std::uninitialized_copy optimizes to memmove, but we can
			// use memcpy here.
			memcpy(Dest, I, (E-I)*sizeof(T));
		}
		
		/// grow - double the size of the allocated memory, guaranteeing space for at
		/// least one more element or MinSize if specified.
		void grow(size_t MinSize = 0) {
			this->grow_pod(MinSize*sizeof(T), sizeof(T));
		}
	};
	
	
	/// SmallVectorImpl - This class consists of common code factored out of the
	/// SmallVector class to reduce code duplication based on the SmallVector 'N'
	/// template parameter.
	template <typename T>
	class SmallVectorImpl : public SmallVectorTemplateBase<T, isPodLike<T>::value> {
		typedef SmallVectorTemplateBase<T, isPodLike<T>::value > SuperClass;
		
		SmallVectorImpl(const SmallVectorImpl&); // DISABLED.
	public:
		typedef typename SuperClass::iterator iterator;
		typedef typename SuperClass::size_type size_type;
		
		// Default ctor - Initialize to empty.
		explicit SmallVectorImpl(unsigned N)
		: SmallVectorTemplateBase<T, isPodLike<T>::value>(N*sizeof(T)) {
		}
		
		~SmallVectorImpl() {
			// Destroy the constructed elements in the vector.
			this->destroy_range(this->begin(), this->end());
			
			// If this wasn't grown from the inline copy, deallocate the old space.
			if (!this->isSmall())
				free(this->begin());
		}
		
		
		void clear() {
			this->destroy_range(this->begin(), this->end());
			this->EndX = this->BeginX;
		}
		
		void resize(unsigned N) {
			if (N < this->size()) {
				this->destroy_range(this->begin()+N, this->end());
				this->setEnd(this->begin()+N);
			} else if (N > this->size()) {
				if (this->capacity() < N)
					this->grow(N);
				this->construct_range(this->end(), this->begin()+N, T());
				this->setEnd(this->begin()+N);
			}
		}
		
		void resize(unsigned N, const T &NV) {
			if (N < this->size()) {
				this->destroy_range(this->begin()+N, this->end());
				this->setEnd(this->begin()+N);
			} else if (N > this->size()) {
				if (this->capacity() < N)
					this->grow(N);
				construct_range(this->end(), this->begin()+N, NV);
				this->setEnd(this->begin()+N);
			}
		}
		
		void reserve(unsigned N) {
			if (this->capacity() < N)
				this->grow(N);
		}
		
		void push_back(const T &Elt) {
			if (this->EndX < this->CapacityX) {
			Retry:
				new (this->end()) T(Elt);
				this->setEnd(this->end()+1);
				return;
			}
			this->grow();
			goto Retry;
		}
		
		void pop_back() {
			this->setEnd(this->end()-1);
			this->end()->~T();
		}
		
		T pop_back_val() {
			T Result = this->back();
			pop_back();
			return Result;
		}
		
		void swap(SmallVectorImpl &RHS);
		
		/// append - Add the specified range to the end of the SmallVector.
		///
		template<typename in_iter>
		void append(in_iter in_start, in_iter in_end) {
			size_type NumInputs = std::distance(in_start, in_end);
			// Grow allocated space if needed.
			if (NumInputs > size_type(this->capacity_ptr()-this->end()))
				this->grow(this->size()+NumInputs);
			
			// Copy the new elements over.
			// TODO: NEED To compile time dispatch on whether in_iter is a random access
			// iterator to use the fast uninitialized_copy.
			std::uninitialized_copy(in_start, in_end, this->end());
			this->setEnd(this->end() + NumInputs);
		}
		
		/// append - Add the specified range to the end of the SmallVector.
		///
		void append(size_type NumInputs, const T &Elt) {
			// Grow allocated space if needed.
			if (NumInputs > size_type(this->capacity_ptr()-this->end()))
				this->grow(this->size()+NumInputs);
			
			// Copy the new elements over.
			std::uninitialized_fill_n(this->end(), NumInputs, Elt);
			this->setEnd(this->end() + NumInputs);
		}
		
		void assign(unsigned NumElts, const T &Elt) {
			clear();
			if (this->capacity() < NumElts)
				this->grow(NumElts);
			this->setEnd(this->begin()+NumElts);
			construct_range(this->begin(), this->end(), Elt);
		}
		
		iterator erase(iterator I) {
			iterator N = I;
			// Shift all elts down one.
			std::copy(I+1, this->end(), I);
			// Drop the last elt.
			pop_back();
			return(N);
		}
		
		iterator erase(iterator S, iterator E) {
			iterator N = S;
			// Shift all elts down.
			iterator I = std::copy(E, this->end(), S);
			// Drop the last elts.
			this->destroy_range(I, this->end());
			this->setEnd(I);
			return(N);
		}
		
		iterator insert(iterator I, const T &Elt) {
			if (I == this->end()) {  // Important special case for empty vector.
				push_back(Elt);
				return this->end()-1;
			}
			
			if (this->EndX < this->CapacityX) {
			Retry:
				new (this->end()) T(this->back());
				this->setEnd(this->end()+1);
				// Push everything else over.
				std::copy_backward(I, this->end()-1, this->end());
				*I = Elt;
				return I;
			}
			size_t EltNo = I-this->begin();
			this->grow();
			I = this->begin()+EltNo;
			goto Retry;
		}
		
		iterator insert(iterator I, size_type NumToInsert, const T &Elt) {
			if (I == this->end()) {  // Important special case for empty vector.
				append(NumToInsert, Elt);
				return this->end()-1;
			}
			
			// Convert iterator to elt# to avoid invalidating iterator when we reserve()
			size_t InsertElt = I - this->begin();
			
			// Ensure there is enough space.
			reserve(static_cast<unsigned>(this->size() + NumToInsert));
			
			// Uninvalidate the iterator.
			I = this->begin()+InsertElt;
			
			// If there are more elements between the insertion point and the end of the
			// range than there are being inserted, we can use a simple approach to
			// insertion.  Since we already reserved space, we know that this won't
			// reallocate the vector.
			if (size_t(this->end()-I) >= NumToInsert) {
				T *OldEnd = this->end();
				append(this->end()-NumToInsert, this->end());
				
				// Copy the existing elements that get replaced.
				std::copy_backward(I, OldEnd-NumToInsert, OldEnd);
				
				std::fill_n(I, NumToInsert, Elt);
				return I;
			}
			
			// Otherwise, we're inserting more elements than exist already, and we're
			// not inserting at the end.
			
			// Copy over the elements that we're about to overwrite.
			T *OldEnd = this->end();
			this->setEnd(this->end() + NumToInsert);
			size_t NumOverwritten = OldEnd-I;
			this->uninitialized_copy(I, OldEnd, this->end()-NumOverwritten);
			
			// Replace the overwritten part.
			std::fill_n(I, NumOverwritten, Elt);
			
			// Insert the non-overwritten middle part.
			std::uninitialized_fill_n(OldEnd, NumToInsert-NumOverwritten, Elt);
			return I;
		}
		
		template<typename ItTy>
		iterator insert(iterator I, ItTy From, ItTy To) {
			if (I == this->end()) {  // Important special case for empty vector.
				append(From, To);
				return this->end()-1;
			}
			
			size_t NumToInsert = std::distance(From, To);
			// Convert iterator to elt# to avoid invalidating iterator when we reserve()
			size_t InsertElt = I - this->begin();
			
			// Ensure there is enough space.
			reserve(static_cast<unsigned>(this->size() + NumToInsert));
			
			// Uninvalidate the iterator.
			I = this->begin()+InsertElt;
			
			// If there are more elements between the insertion point and the end of the
			// range than there are being inserted, we can use a simple approach to
			// insertion.  Since we already reserved space, we know that this won't
			// reallocate the vector.
			if (size_t(this->end()-I) >= NumToInsert) {
				T *OldEnd = this->end();
				append(this->end()-NumToInsert, this->end());
				
				// Copy the existing elements that get replaced.
				std::copy_backward(I, OldEnd-NumToInsert, OldEnd);
				
				std::copy(From, To, I);
				return I;
			}
			
			// Otherwise, we're inserting more elements than exist already, and we're
			// not inserting at the end.
			
			// Copy over the elements that we're about to overwrite.
			T *OldEnd = this->end();
			this->setEnd(this->end() + NumToInsert);
			size_t NumOverwritten = OldEnd-I;
			this->uninitialized_copy(I, OldEnd, this->end()-NumOverwritten);
			
			// Replace the overwritten part.
			for (; NumOverwritten > 0; --NumOverwritten) {
				*I = *From;
				++I; ++From;
			}
			
			// Insert the non-overwritten middle part.
			this->uninitialized_copy(From, To, OldEnd);
			return I;
		}
		
		const SmallVectorImpl
		&operator=(const SmallVectorImpl &RHS);
		
		bool operator==(const SmallVectorImpl &RHS) const {
			if (this->size() != RHS.size()) return false;
			return std::equal(this->begin(), this->end(), RHS.begin());
		}
		bool operator!=(const SmallVectorImpl &RHS) const {
			return !(*this == RHS);
		}
		
		bool operator<(const SmallVectorImpl &RHS) const {
			return std::lexicographical_compare(this->begin(), this->end(),
												RHS.begin(), RHS.end());
		}
		
		/// set_size - Set the array size to \arg N, which the current array must have
		/// enough capacity for.
		///
		/// This does not construct or destroy any elements in the vector.
		///
		/// Clients can use this in conjunction with capacity() to write past the end
		/// of the buffer when they know that more elements are available, and only
		/// update the size later. This avoids the cost of value initializing elements
		/// which will only be overwritten.
		void set_size(unsigned N) {
			assert(N <= this->capacity());
			this->setEnd(this->begin() + N);
		}
		
	private:
		static void construct_range(T *S, T *E, const T &Elt) {
			for (; S != E; ++S)
				new (S) T(Elt);
		}
	};
	
	
	template <typename T>
	void SmallVectorImpl<T>::swap(SmallVectorImpl<T> &RHS) {
		if (this == &RHS) return;
		
		// We can only avoid copying elements if neither vector is small.
		if (!this->isSmall() && !RHS.isSmall()) {
			std::swap(this->BeginX, RHS.BeginX);
			std::swap(this->EndX, RHS.EndX);
			std::swap(this->CapacityX, RHS.CapacityX);
			return;
		}
		if (RHS.size() > this->capacity())
			this->grow(RHS.size());
		if (this->size() > RHS.capacity())
			RHS.grow(this->size());
		
		// Swap the shared elements.
		size_t NumShared = this->size();
		if (NumShared > RHS.size()) NumShared = RHS.size();
		for (unsigned i = 0; i != static_cast<unsigned>(NumShared); ++i)
			std::swap((*this)[i], RHS[i]);
		
		// Copy over the extra elts.
		if (this->size() > RHS.size()) {
			size_t EltDiff = this->size() - RHS.size();
			this->uninitialized_copy(this->begin()+NumShared, this->end(), RHS.end());
			RHS.setEnd(RHS.end()+EltDiff);
			this->destroy_range(this->begin()+NumShared, this->end());
			this->setEnd(this->begin()+NumShared);
		} else if (RHS.size() > this->size()) {
			size_t EltDiff = RHS.size() - this->size();
			this->uninitialized_copy(RHS.begin()+NumShared, RHS.end(), this->end());
			this->setEnd(this->end() + EltDiff);
			this->destroy_range(RHS.begin()+NumShared, RHS.end());
			RHS.setEnd(RHS.begin()+NumShared);
		}
	}
	
	template <typename T>
	const SmallVectorImpl<T> &SmallVectorImpl<T>::
	operator=(const SmallVectorImpl<T> &RHS) {
		// Avoid self-assignment.
		if (this == &RHS) return *this;
		
		// If we already have sufficient space, assign the common elements, then
		// destroy any excess.
		size_t RHSSize = RHS.size();
		size_t CurSize = this->size();
		if (CurSize >= RHSSize) {
			// Assign common elements.
			iterator NewEnd;
			if (RHSSize)
				NewEnd = std::copy(RHS.begin(), RHS.begin()+RHSSize, this->begin());
			else
				NewEnd = this->begin();
			
			// Destroy excess elements.
			this->destroy_range(NewEnd, this->end());
			
			// Trim.
			this->setEnd(NewEnd);
			return *this;
		}
		
		// If we have to grow to have enough elements, destroy the current elements.
		// This allows us to avoid copying them during the grow.
		if (this->capacity() < RHSSize) {
			// Destroy current elements.
			this->destroy_range(this->begin(), this->end());
			this->setEnd(this->begin());
			CurSize = 0;
			this->grow(RHSSize);
		} else if (CurSize) {
			// Otherwise, use assignment for the already-constructed elements.
			std::copy(RHS.begin(), RHS.begin()+CurSize, this->begin());
		}
		
		// Copy construct the new elements in place.
		this->uninitialized_copy(RHS.begin()+CurSize, RHS.end(),
								 this->begin()+CurSize);
		
		// Set end.
		this->setEnd(this->begin()+RHSSize);
		return *this;
	}
	
	
	/// SmallVector - This is a 'vector' (really, a variable-sized array), optimized
	/// for the case when the array is small.  It contains some number of elements
	/// in-place, which allows it to avoid heap allocation when the actual number of
	/// elements is below that threshold.  This allows normal "small" cases to be
	/// fast without losing generality for large inputs.
	///
	/// Note that this does not attempt to be exception safe.
	///
	template <typename T, unsigned N>
	class SmallVector : public SmallVectorImpl<T> {
		/// InlineElts - These are 'N-1' elements that are stored inline in the body
		/// of the vector.  The extra '1' element is stored in SmallVectorImpl.
		typedef typename SmallVectorImpl<T>::U U;
		enum {
			// MinUs - The number of U's require to cover N T's.
			MinUs = (static_cast<unsigned int>(sizeof(T))*N +
					 static_cast<unsigned int>(sizeof(U)) - 1) /
            static_cast<unsigned int>(sizeof(U)),
			
			// NumInlineEltsElts - The number of elements actually in this array.  There
			// is already one in the parent class, and we have to round up to avoid
			// having a zero-element array.
			NumInlineEltsElts = MinUs > 1 ? (MinUs - 1) : 1,
			
			// NumTsAvailable - The number of T's we actually have space for, which may
			// be more than N due to rounding.
			NumTsAvailable = (NumInlineEltsElts+1)*static_cast<unsigned int>(sizeof(U))/
			static_cast<unsigned int>(sizeof(T))
		};
		U InlineElts[NumInlineEltsElts];
	public:
		SmallVector() : SmallVectorImpl<T>(NumTsAvailable) {
		}
		
		explicit SmallVector(unsigned Size, const T &Value = T())
		: SmallVectorImpl<T>(NumTsAvailable) {
			this->reserve(Size);
			while (Size--)
				this->push_back(Value);
		}
		
		template<typename ItTy>
		SmallVector(ItTy S, ItTy E) : SmallVectorImpl<T>(NumTsAvailable) {
			this->append(S, E);
		}
		
		SmallVector(const SmallVector &RHS) : SmallVectorImpl<T>(NumTsAvailable) {
			if (!RHS.empty())
				SmallVectorImpl<T>::operator=(RHS);
		}
		
		const SmallVector &operator=(const SmallVector &RHS) {
			SmallVectorImpl<T>::operator=(RHS);
			return *this;
		}
		
	};

/// Specialize SmallVector at N=0.  This specialization guarantees
/// that it can be instantiated at an incomplete T if none of its
/// members are required.
template <typename T>
class SmallVector<T,0> : public SmallVectorImpl<T> {
public:
  SmallVector() : SmallVectorImpl<T>(0) {}

  explicit SmallVector(unsigned Size, const T &Value = T())
    : SmallVectorImpl<T>(0) {
    this->reserve(Size);
    while (Size--)
      this->push_back(Value);
  }

  template<typename ItTy>
  SmallVector(ItTy S, ItTy E) : SmallVectorImpl<T>(0) {
    this->append(S, E);
  }

  SmallVector(const SmallVector &RHS) : SmallVectorImpl<T>(0) {
    SmallVectorImpl<T>::operator=(RHS);
  }

  SmallVector &operator=(const SmallVectorImpl<T> &RHS) {
    return SmallVectorImpl<T>::operator=(RHS);
  }

};

} // End Ogre namespace

namespace std {
	/// Implement std::swap in terms of SmallVector swap.
	template<typename T>
	inline void
	swap(Ogre::SmallVectorImpl<T> &LHS, Ogre::SmallVectorImpl<T> &RHS) {
		LHS.swap(RHS);
	}
	
	/// Implement std::swap in terms of SmallVector swap.
	template<typename T, unsigned N>
	inline void
	swap(Ogre::SmallVector<T, N> &LHS, Ogre::SmallVector<T, N> &RHS) {
		LHS.swap(RHS);
	}
}

#endif