This is Q-Graph, a graph library and editor for the Q programming language.
The package contains:

- graph.q: a graph data structure implemented as a kind of asymmetric
  adjacency list dictionary, and a collection of the usual graph operations

- graphed.q: a full-featured graph editor, allows you to create and edit your
  input graphs with ease (requires Tcl/Tk)

WWW: http://q-lang.sourceforge.net