Fix fixed-depth iterator

ChangeLog

@@ -1,3 +1,10 @@
+2018-04-23  Kasper Peeters  <kasper.peeters@phi-sci.com>
+
+	* Release 3.8.
+
+	* Make fixed-depth iterators start at the first node in a range of
+	siblings.
+
 2018-01-30  Kasper Peeters  <kasper.peeters@phi-sci.com>
 
 	* Release 3.6.

examples/iterate_head.cc

@@ -0,0 +1,22 @@
+#include "tree.hh"
+#include <iostream>
+
+// This example shows how to iterate over the head nodes
+// of a tree only. 
+
+int main(int, char **)
+   {
+   tree<std::string> t;
+
+   t.set_head("one");
+   auto i2 = t.insert(t.end(), "two");
+   auto i3 = t.insert(t.end(), "three");
+   t.append_child(i2, "apple");
+   t.append_child(i2, "pear");   
+   t.append_child(i3, "banana");
+   t.append_child(i3, "kiwi");   
+
+   tree<std::string>::sibling_iterator it=t.begin();
+   while(it!=t.end())
+	   std::cerr << (*it++) << std::endl;
+   }

examples/move_subtree.cc

@@ -0,0 +1,33 @@
+#include <iostream>
+#include "tree.hh"
+#include "tree_util.hh"
+
+void print_tree(const tree<std::string>& tr)
+{
+    tree<std::string>::pre_order_iterator it = tr.begin();
+    tree<std::string>::pre_order_iterator end = tr.end();
+    if(!tr.is_valid(it)) return;
+    int rootdepth=tr.depth(it);
+    std::cout << "-----" << std::endl;
+    while(it!=end) {
+        for(int i=0; i<tr.depth(it)-rootdepth; ++i)
+            std::cout << "  ";
+        std::cout << (*it) << std::endl << std::flush;
+        ++it;
+        }
+    std::cout << "-----" << std::endl;
+}
+
+int main(int, char **)
+{
+    tree<std::string> my_tree;
+
+    tree<std::string>::iterator iA = my_tree.insert(my_tree.end(), "A");
+    tree<std::string>::iterator iB = my_tree.insert(my_tree.end(), "B");
+    tree<std::string>::iterator iB1 = my_tree.append_child(iB, "B1");
+    tree<std::string>::iterator iC = my_tree.insert(my_tree.end(), "C");        
+    print_tree(my_tree);
+
+    my_tree.move_after(iB1, iC);
+    print_tree(my_tree);
+}

src/test_tree.cc

@@ -365,6 +365,22 @@ int main(int argc, char **argv)
 			 ++li;
 			 }
 
+		// Fixed-depth.
+		tree<std::string> fdt;
+		fdt.set_head("beings");
+		auto mammals = fdt.append_child(fdt.begin(), "mammals");
+		fdt.append_child(fdt.begin(), "birds");
+		fdt.append_child(mammals, "human");
+		auto felins = fdt.append_child(mammals, "felins");
+		fdt.append_child(mammals, "canids");
+		fdt.append_child(felins, "cats");
+
+		auto fi = tr.begin_fixed(felins, 0);
+		while(fdt.is_valid(fi)) {
+			std::cout << *fi << std::endl;
+			++fi;
+			}
+
 //		test_move_constructor();
 
 		}

src/tree.hh

@@ -9,8 +9,8 @@
 
 /** \mainpage tree.hh
     \author   Kasper Peeters
-    \version  3.7
-    \date     30-Jan-2018
+    \version  3.8
+    \date     23-Apr-2018
     \see      http://tree.phi-sci.com/
     \see      http://tree.phi-sci.com/ChangeLog
 
@@ -792,6 +792,10 @@ typename tree<T, tree_node_allocator>::fixed_depth_iterator tree<T, tree_node_al
 		++curdepth;
 		}
 
+	// Now walk back to the first sibling in this range.
+	while(tmp->prev_sibling!=0)
+		tmp=tmp->prev_sibling;	
+
 	ret.node=tmp;
 	return ret;
 	}