Made parse_trees_to_string() and parse_trees_to_string_tagged() a little more

user friendly.

dlib/optimization/find_max_parse_cky.h

@@ -340,14 +340,14 @@ namespace dlib
     std::string parse_trees_to_string (
         const std::vector<parse_tree_element<T> >& tree,
         const std::vector<U>& words,
-        const unsigned long root_idx = 0
+        const T& tag_to_skip
     )
     {
-        if (root_idx >= tree.size())
+        if (tree.size() == 0)
             return "";
 
         std::ostringstream sout;
-        impl::print_parse_tree_helper<false,true>(tree, words, root_idx, tree[root_idx].tag, sout);
+        impl::print_parse_tree_helper<false,true>(tree, words, 0, tag_to_skip, sout);
         return sout.str();
     }
 
@@ -357,14 +357,14 @@ namespace dlib
     std::string parse_trees_to_string_tagged (
         const std::vector<parse_tree_element<T> >& tree,
         const std::vector<U>& words,
-        const unsigned long root_idx = 0
+        const T& tag_to_skip
     )
     {
-        if (root_idx >= tree.size())
+        if (tree.size() == 0)
             return "";
 
         std::ostringstream sout;
-        impl::print_parse_tree_helper<true,true>(tree, words, root_idx, tree[root_idx].tag, sout);
+        impl::print_parse_tree_helper<true,true>(tree, words, 0, tag_to_skip, sout);
         return sout.str();
     }
 

dlib/optimization/find_max_parse_cky_abstract.h

@@ -298,7 +298,7 @@ namespace dlib
     std::string parse_trees_to_string (
         const std::vector<parse_tree_element<T> >& tree,
         const std::vector<U>& words,
-        const unsigned long root_idx = 0
+        const T& tag_to_skip
     );
     /*!
         requires
@@ -307,9 +307,9 @@ namespace dlib
         ensures
             - This function behaves just like parse_tree_to_string() except that it will
               not print the brackets (i.e. []) for the top most parts of the tree which
-              have tags equal to tree[root_idx].tag.  It will however print all the words.
+              have tags equal to tag_to_skip.  It will however print all the words.
               Therefore, this function only includes brackets on the subtrees which begin
-              with a tag other than tree[root_idx].tag.
+              with a tag other than tag_to_skip.
         throws
             - parse_tree_to_string_error
                 This exception is thrown if an invalid tree is detected.  This might happen
@@ -326,7 +326,7 @@ namespace dlib
     std::string parse_trees_to_string_tagged (
         const std::vector<parse_tree_element<T> >& tree,
         const std::vector<U>& words,
-        const unsigned long root_idx = 0
+        const T& tag_to_skip
     );
     /*!
         requires
@@ -336,9 +336,9 @@ namespace dlib
         ensures
             - This function behaves just like parse_tree_to_string_tagged() except that it
               will not print the brackets (i.e. []) for the top most parts of the tree
-              which have tags equal to tree[root_idx].tag.  It will however print all the
-              words.  Therefore, this function only includes brackets on the subtrees which
-              begin with a tag other than tree[root_idx].tag.
+              which have tags equal to tag_to_skip.  It will however print all the words.
+              Therefore, this function only includes brackets on the subtrees which begin
+              with a tag other than tag_to_skip.
         throws
             - parse_tree_to_string_error
                 This exception is thrown if an invalid tree is detected.  This might happen

dlib/test/parse.cpp

@@ -131,10 +131,10 @@ namespace
 
         const std::string str3 = "[[The flight] [includes [a meal]]] [[The flight] [includes [a meal]]]";
         const std::string str4 = "[5 [3 The flight] [4 includes [3 a meal]]] [5 [3 The flight] [4 includes [3 a meal]]]";
-        dlog << LINFO << parse_trees_to_string(parse_tree, words);
-        DLIB_TEST(parse_trees_to_string(parse_tree, words) == str3);
-        dlog << LINFO << parse_trees_to_string_tagged(parse_tree, words);
-        DLIB_TEST(parse_trees_to_string_tagged(parse_tree, words) == str4);
+        dlog << LINFO << parse_trees_to_string(parse_tree, words, G);
+        DLIB_TEST(parse_trees_to_string(parse_tree, words, G) == str3);
+        dlog << LINFO << parse_trees_to_string_tagged(parse_tree, words, G);
+        DLIB_TEST(parse_trees_to_string_tagged(parse_tree, words, G) == str4);
 
         sequence.clear();
         find_max_parse_cky(sequence, user_defined_ruleset<true>, parse_tree);