// -*- C++ -*-
+/**
+ * \file lyxalgo.h
+ * This file is part of LyX, the document processor.
+ * Licence details can be found in the file COPYING.
+ *
+ * \author Lars Gullik Bjønnes
+ *
+ * Full author contact details are available in file CREDITS.
+ *
+ * A variety of useful templates.
+ */
#ifndef LYX_ALGO_H
#define LYX_ALGO_H
+#include <utility>
+#include <iterator>
#include <algorithm>
-// using std::less;
-// Both these functions should ideally be placed into namespace lyx.
-// Also the using std::less should not be used.
+namespace lyx {
-//namespace lyx {
/// Returns true if the sequence first,last is sorted, false if not.
template <class For>
if (first == last) return true;
For tmp = first;
while (++tmp != last) {
- if (less(*tmp, *first++)) return false;
+ if (*tmp < *first++) return false;
}
return true;
}
+
/// Cmp is the same Cmp as you would pass to std::sort.
template <class For, class Cmp>
bool sorted(For first, For last, Cmp cmp)
return true;
}
-// } // end of namespace lyx
+
+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;
+}
+
+
+/// A slot in replacement for std::count for systems where it is broken.
+template <class Iterator, class T>
+typename std::iterator_traits<Iterator>::difference_type
+count (Iterator first, Iterator last, T const & value)
+{
+#ifdef HAVE_STD_COUNT
+ return std::count(first, last, value);
+#else
+ typename std::iterator_traits<Iterator>::difference_type n = 0;
+ while (first != last)
+ if (*first++ == value) ++n;
+ return n;
#endif
+}
+
+/// 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