Constify State::RootNodes().

2 files changed, 7 insertions, 6 deletions

diff --git a/src/state.cc b/src/state.cc
index a70f211..d539e7b 100644
--- a/src/state.cc
+++ b/src/state.cc
@@ -159,11 +159,12 @@ bool State::AddDefault(StringPiece path, string* err) {
   return true;
 }
 
-vector<Node*> State::RootNodes(string* err) {
+vector<Node*> State::RootNodes(string* err) const {
   vector<Node*> root_nodes;
   // Search for nodes with no output.
-  for (vector<Edge*>::iterator e = edges_.begin(); e != edges_.end(); ++e) {
-    for (vector<Node*>::iterator out = (*e)->outputs_.begin();
+  for (vector<Edge*>::const_iterator e = edges_.begin();
+       e != edges_.end(); ++e) {
+    for (vector<Node*>::const_iterator out = (*e)->outputs_.begin();
          out != (*e)->outputs_.end(); ++out) {
       if ((*out)->out_edges().empty())
         root_nodes.push_back(*out);
@@ -176,7 +177,7 @@ vector<Node*> State::RootNodes(string* err) {
   return root_nodes;
 }
 
-vector<Node*> State::DefaultNodes(string* err) {
+vector<Node*> State::DefaultNodes(string* err) const {
   return defaults_.empty() ? RootNodes(err) : defaults_;
 }
 
diff --git a/src/state.h b/src/state.h
index d7987ba..b530207 100644
--- a/src/state.h
+++ b/src/state.h
@@ -110,8 +110,8 @@ struct State {
 
   /// @return the root node(s) of the graph. (Root nodes have no output edges).
   /// @param error where to write the error message if somethings went wrong.
-  vector<Node*> RootNodes(string* error);
-  vector<Node*> DefaultNodes(string* error);
+  vector<Node*> RootNodes(string* error) const;
+  vector<Node*> DefaultNodes(string* error) const;
 
   /// Mapping of path -> Node.
   typedef ExternalStringHashMap<Node*>::Type Paths;