Re: [Boost-users] property map: does a given key exist?

From: Daniel Mitchell (danmitchell_at_[hidden])
Date: 2006-04-16 23:37:03

On Saturday 15 April 2006 15:25, Irek Szczesniak wrote:
> In nutshell: how can I check whether a property map has some given
> key?

Some property maps may provide bounds checking, but the property map concept 
doesn't require it, so in general you can't.

>
> graph {
>    a;
>    b;
>    c;
>    c -- a [distance="100"];
>    a -- b [lambdas="8"];
> }
>

I think you'll need to give every edge a lambda number, but you might reserve 
a special value to indicate that the lambda property isn't applicable to that 
edge.

Daniel