added debug example and fix dump error

Tsung-Wei Huang · Tsung-Wei Huang · commit 7b5640e34afe · 2018-06-23T16:04:43.000-05:00
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -57,6 +57,9 @@ message(STATUS "EXAMPLE_EXE_LINKER_FLAGS: " ${EXAMPLE_EXE_LINKER_FLAGS})
 add_executable(simple example/simple.cpp)
 target_link_libraries(simple ${EXAMPLE_EXE_LINKER_FLAGS})
 
+add_executable(debug example/debug.cpp)
+target_link_libraries(debug ${EXAMPLE_EXE_LINKER_FLAGS})
+
 add_executable(matrix example/matrix.cpp)
 target_compile_options(matrix PRIVATE ${EXAMPLE_CXX_FLAGS})
 target_link_libraries(matrix ${EXAMPLE_EXE_LINKER_FLAGS})
diff --git a/README.md b/README.md
@@ -471,6 +471,7 @@ The folder `example/` contains several examples and is a great place to learn to
 | [simple.cpp](./example/simple.cpp) | use basic task building blocks to create a trivial taskflow  graph |
 | [matrix.cpp](./example/matrix.cpp) | create two set of matrices and multiply each individually in parallel |
 | [parallel_for.cpp](./example/parallel_for.cpp)| parallelize a for loop with unbalanced workload |
+| [debug.cpp](./example/debug.cpp)| inspect a taskflow through the dump method |
 
 # Get Involved
 + Report bugs/issues by submitting a [Github issue][Github issues].
diff --git a/example/debug.cpp b/example/debug.cpp
@@ -0,0 +1,34 @@
+// This example demonstrates how to use 'dump' method to inspect 
+// a taskflow graph.
+
+#include "taskflow.hpp"
+
+int main(){
+
+  tf::Taskflow tf;
+
+  auto [A, B, C, D, E] = tf.silent_emplace(
+    [] () { std::cout << "Task A" << std::endl; },
+    [] () { std::cout << "Task B" << std::endl; },
+    [] () { std::cout << "Task C" << std::endl; },
+    [] () { std::cout << "Task D" << std::endl; },
+    [] () { std::cout << "Task E" << std::endl; }
+  );
+
+  A.broadcast(B, C, E); 
+  C.precede(D);
+  B.broadcast(D, E); 
+  
+  std::cout << "dumpe without name assignment\n";
+  std::cout << tf.dump() << std::endl;
+  
+  std::cout << "dumpe with name assignment\n";
+  A.name("A");
+  B.name("B");
+  C.name("C");
+  D.name("D");
+  E.name("E");
+  std::cout << tf.dump() << std::endl;
+
+  return 0;
+}
diff --git a/taskflow.hpp b/taskflow.hpp
@@ -39,6 +39,7 @@
 #include <list>
 #include <forward_list>
 #include <numeric>
+#include <iomanip>
 
 namespace tf {
 
@@ -1032,18 +1033,26 @@ std::string BasicTaskflow<F>::dump() const {
   os << "digraph Taskflow {\n";
   
   for(const auto& node : _nodes) {
-
-    os << "  \"" << (node.name().empty() ? &node : node.name()) << "\";\n";
+    
+    if(node.name().empty()) os << '\"' << &node << '\"';
+    else os << std::quoted(node.name());
+    os << ";\n";
 
     for(const auto s : node._successors) {
-      os << "  \"" << (node.name().empty() ? &node : node.name())
-      << "\" -> \""
-      << (s->name().empty() ? s : s->name())
-      << "\";\n";
+
+      if(node.name().empty()) os << '\"' << &node << '\"';
+      else os << std::quoted(node.name());
+
+      os << " -> ";
+      
+      if(s->name().empty()) os << '\"' << &node << '\"';
+      else os << std::quoted(s->name());
+
+      os << ";\n";
     }
   }
 
-  os << "}\n";
+  os << "}";
   
   return os.str();
 }
