diff --git a/libs/main/containers/pivector.h b/libs/main/containers/pivector.h
index 97f99453..d62989a0 100644
--- a/libs/main/containers/pivector.h
+++ b/libs/main/containers/pivector.h
@@ -283,6 +283,12 @@ public:
 	inline T * data(size_t index = 0) {return &(piv_data[index]);}
 	inline const T * data(size_t index = 0) const {return &(piv_data[index]);}
 
+	PIVector<T> getRange(size_t index, size_t count) const {
+		if (index >= piv_size || count == 0) return PIVector<T>();
+		if (index + count > piv_size) count = piv_size - index;
+		return PIVector(&(piv_data[index]), count);
+	}
+
 	template<typename T1 = T, typename std::enable_if<
 				 !std::is_trivially_copyable<T1>::value
 				 , int>::type = 0>
@@ -462,7 +468,6 @@ public:
 		}
 		return *this;
 	}
-
 	inline PIVector<T> & removeAll(const T & e) {
 		for (ssize_t i = 0; i < ssize_t(piv_size); ++i) {
 			if (piv_data[i] == e) {
@@ -472,6 +477,15 @@ public:
 		}
 		return *this;
 	}
+	inline PIVector<T> & removeWhere(std::function<bool(const T & e)> test) {
+		for (ssize_t i = 0; i < ssize_t(piv_size); ++i) {
+			if (test(piv_data[i])) {
+				remove(i);
+				--i;
+			}
+		}
+		return *this;
+	}
 
 	inline PIVector<T> & push_back(const T & e) {
 		alloc(piv_size + 1);