The standard library planar_graphtree package is part of the graph-visualization support infrastructure.
The planar_graphtree package implements the Traitful_Graphtree api.
The planar_graphtree package source code is in src/lib/std/dot/planar-graphtree.pkg.
See also: planar_graphtree_traits package.
The above information is manually maintained and may contain errors.
Traitful_Graphtree