find only files that load libraries
local -a files package_sources_or_args files "$@"
TODO: rename these symbols and eliminate these placeholders
dep_graph()
Generates graphviz source code in the named file ($1) that will produce the specified kind ($2) of package dependency graph.
$1 - Output file that will contain the required 'dot' graphing commands
$2 - Kind of package graph (all, tools, libs, runtime, or files)
avoid graphs cycles
display tool different
only display the include the runtime when indicated