----- Original Message -----
From: Tarjei Knapstad
A possibility (as have recently been discussed IIRC) is to break off the DFS by throwing an exception the second time start_vertex is invoked in the visitor. I'm not too fond of that solution though, allthough I must admit that my visitor implementation above is not exactly "a beaut"...
A less drastic alternative is to, on the second call, just set all vertex colours to black. But I agree with you that a one_shot_depth_first_search that starts from a given vertex and then gets out is called for. In fact I find it difficult to understand why anyone would want to start at a given vertex, do a dfs from there and then go on to start another dfs from any unvisited vertices. Perhaps I lack imagination - anyone got an example of its use? Louis.