+
+struct firster {
+ template <class P1, class P2>
+ P1 operator()(std::pair<P1, P2> const & p) {
+ return p.first;
+ }
+};
+
+
+/**
+ * copy elements in the given range to the output iterator
+ * if the predicate evaluates as true
+ */
+template <class InputIter, class OutputIter, class Func>
+OutputIter copy_if(InputIter first, InputIter last,
+ OutputIter result, Func func)
+{
+ for (; first != last; ++first) {
+ if (func(*first)) {
+ *result++ = *first;
+ }
+ }
+ return result;
+}
+
+
+/// Remove all duplicate entries in c.
+template<class C>
+void eliminate_duplicates(C & c)
+{
+ // It is a requirement that the container is sorted for
+ // std::unique to work properly.
+ std::sort(c.begin(), c.end());
+ c.erase(std::unique(c.begin(), c.end()), c.end());
+}
+
+
+} // namespace lyx
+
+#endif // LYX_ALGO_H