itree.rb

##!/usr/bin/ruby

# Quick and dirty C++ inheritance tree using GraphViz's dot command
# Limitations:
# * Only handles single inheritance
# * Base classes must be specified on a single line:
#   Such as "class Foo : public Bar"

require "find"
ofile = ARGV.shift
IO.popen("dot -Tsvg -o" + ofile, mode="w") do | dot |
  dot.puts "digraph G {"
  dot.puts "rankdir=BT;"

  ARGV.each do | dir |
    Find.find(dir) do | f |
      Find.prune if f == "."
      # puts "Processing \""  + f + "\""
      if f =~ /\.h$/ then
        IO.foreach(f) do | ln |
          if ln =~ /class *.* +(\w+)\s+:\s+public\s+(\w+)\s*$/ then
            derived = $1
            base = $2
            dot.puts derived + " -> " + base + ";"
          end
        end
      end
    end
  end

  dot.puts "}"
end