# File lib/facets/core/hash/traverse.rb, line 16
  def traverse(&b)
    inject({}) do |h,(k,v)|
      v = ( Hash === v ? v.traverse(&b) : v )
      nk, nv = b[k,v]
      h[nk] = nv #( Hash === v ? v.traverse(base,&b) : nv )
      h
    end
  end