Consider reusing the golang.org/x/tools callgraph libraries and tools

Nice work!  You might be interested in these other libraries and tools that construct the call graph of a Go program:

golang.org/x/tools/go/callgraph
  represents the call graph of a Go program

golang.org/x/tools/cmd/callgraph
  computes the call graph of a program

golang.org/x/tools/cmd/godoc -analysis=pointer
  displays the call graph of  a Go program in a web interface
