[CM] starting node in graph

[Drew Krause]

As part of a 'let' statement I'm writing in CM, I'd like to pass the 
starting node in a graph path as a variable, but am unclear how to do it.

Trying the ":last" slot in the simplest case, I'm stumped because paths 
taken from the graph

(define mygraph (new graph of '((1 :to 2) (2 :to 3) (3 :to 1)) :last 2))

always begin on 1 whenever the graph is initialized. In this case, I 
would like for the first (and only btw) path to always begin on 2.

Any help appreciated!

Drew krause