Lots of stuff

PortabilityLayer/BinarySearch.h

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+#pragma once
+#ifndef __PL_BINARY_SEARCH_H__
+#define __PL_BINARY_SEARCH_H__
+
+#include <stdint.h>
+
+namespace PortabilityLayer
+{
+	template<class TIterator, class TItem, class TPredicate>
+	TIterator BinarySearch(const TIterator &startInclusive, const TIterator &endExclusive, const TItem &item, const TPredicate &pred)
+	{
+		TIterator searchStartInclusive = startInclusive;
+		TIterator searchEndExclusive = endExclusive;
+
+		while (searchStartInclusive != searchEndExclusive)
+		{
+			const ptrdiff_t delta = searchEndExclusive - searchStartInclusive;
+			const ptrdiff_t halfDelta = delta / 2;
+
+			const TIterator midPoint = searchStartInclusive + halfDelta;
+
+			const int comparison = pred(item, *midPoint);
+
+			if (comparison < 0)
+				searchEndExclusive = midPoint;
+			else if (comparison > 0)
+				searchStartInclusive = midPoint + 1;
+			else
+				return midPoint;
+		}
+
+		return endExclusive;
+	}
+}
+
+#endif