StackOverflow2013

Note that there are some explanatory texts on larger screens.

plurals

POSafe way for getting/finding a vertex in a graph with custom properties -> good programming practice?
text
Body
copied!<p>I am writing a Graph-class using boost-graph-library. I use custom vertex and edge properties and a map to store/find the vertices/edges for a given property.<br> I'm satisfied with how it works, so far.<br> However, I have a small problem, where I'm not sure how to solve it "nicely". The class provides a method</p> <pre><code>Vertex getVertex(Vertexproperties v_prop) </code></pre> <p>and a method</p> <pre><code>bool hasVertex(Vertexproperties v_prop) </code></pre> <p>The question now is, would you judge this as good programming practice in C++?<br> My opinion is, that I have first to check if something is available before I can get it. So, before getting a vertex with a desired property, one has to check if hasVertex() would return true for those properties.<br> However, I would like to make getVertex() a bit more robust. ATM it will segfault when one would directly call getVertex() without prior checking if the graph has a corresponding vertex. A first idea was to return a NULL-pointer or a pointer that points <em>past</em> the last stored vertex. For the latter, I haven't found out how to do this.<br> But even with this "robust" version, one would have to check for correctness after getting a vertex or one would also run into a SegFault when dereferencing that vertex-pointer for example. Therefore I am wondering if it is "ok" to let getVertex() SegFault if one does not check for availability beforehand?</p>

Querying!

Guidance

An individual column

Larger individual text columns get their own page to allow for proper reading.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload